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postgresql/src/backend/executor/execIndexing.c

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Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
/*-------------------------------------------------------------------------
*
* execIndexing.c
Add comments explaining how unique and exclusion constraints are enforced.
2015-04-24 20:12:32 +02:00
* routines for inserting index tuples and enforcing unique and
Fix typo in comment. Amit Langote
2016-09-15 17:35:57 +02:00
* exclusion constraints.
Add comments explaining how unique and exclusion constraints are enforced.
2015-04-24 20:12:32 +02:00
*
* ExecInsertIndexTuples() is the main entry point. It's called after
* inserting a tuple to the heap, and it inserts corresponding index tuples
* into all indexes. At the same time, it enforces any unique and
* exclusion constraints:
*
* Unique Indexes
* --------------
*
* Enforcing a unique constraint is straightforward. When the index AM
* inserts the tuple to the index, it also checks that there are no
* conflicting tuples in the index already. It does so atomically, so that
* even if two backends try to insert the same key concurrently, only one
* of them will succeed. All the logic to ensure atomicity, and to wait
* for in-progress transactions to finish, is handled by the index AM.
*
* If a unique constraint is deferred, we request the index AM to not
* throw an error if a conflict is found. Instead, we make note that there
* was a conflict and return the list of indexes with conflicts to the
* caller. The caller must re-check them later, by calling index_insert()
* with the UNIQUE_CHECK_EXISTING option.
*
* Exclusion Constraints
* ---------------------
*
* Exclusion constraints are different from unique indexes in that when the
* tuple is inserted to the index, the index AM does not check for
* duplicate keys at the same time. After the insertion, we perform a
* separate scan on the index to check for conflicting tuples, and if one
* is found, we throw an error and the transaction is aborted. If the
* conflicting tuple's inserter or deleter is in-progress, we wait for it
* to finish first.
*
* There is a chance of deadlock, if two backends insert a tuple at the
* same time, and then perform the scan to check for conflicts. They will
* find each other's tuple, and both try to wait for each other. The
* deadlock detector will detect that, and abort one of the transactions.
* That's fairly harmless, as one of them was bound to abort with a
* "duplicate key error" anyway, although you get a different error
* message.
*
* If an exclusion constraint is deferred, we still perform the conflict
* checking scan immediately after inserting the index tuple. But instead
* of throwing an error if a conflict is found, we return that information
* to the caller. The caller must re-check them later by calling
* check_exclusion_constraint().
*
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* Speculative insertion
* ---------------------
*
Collection of typo fixes. Use "a" and "an" correctly, mostly in comments. Two error messages were also fixed (they were just elogs, so no translation work required). Two function comments in pg_proc.h were also fixed. Etsuro Fujita reported one of these, but I found a lot more with grep. Also fix a few other typos spotted while grepping for the a/an typos. For example, "consists out of ..." -> "consists of ...". Plus a "though"/ "through" mixup reported by Euler Taveira. Many of these typos were in old code, which would be nice to backpatch to make future backpatching easier. But much of the code was new, and I didn't feel like crafting separate patches for each branch. So no backpatching.
2015-05-20 15:18:11 +02:00
* Speculative insertion is a two-phase mechanism used to implement
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* INSERT ... ON CONFLICT DO UPDATE/NOTHING. The tuple is first inserted
* to the heap and update the indexes as usual, but if a constraint is
* violated, we can still back out the insertion without aborting the whole
* transaction. In an INSERT ... ON CONFLICT statement, if a conflict is
* detected, the inserted tuple is backed out and the ON CONFLICT action is
* executed instead.
*
* Insertion to a unique index works as usual: the index AM checks for
* duplicate keys atomically with the insertion. But instead of throwing
* an error on a conflict, the speculatively inserted heap tuple is backed
* out.
*
* Exclusion constraints are slightly more complicated. As mentioned
* earlier, there is a risk of deadlock when two backends insert the same
* key concurrently. That was not a problem for regular insertions, when
* one of the transactions has to be aborted anyway, but with a speculative
* insertion we cannot let a deadlock happen, because we only want to back
* out the speculatively inserted tuple on conflict, not abort the whole
* transaction.
*
* When a backend detects that the speculative insertion conflicts with
* another in-progress tuple, it has two options:
*
* 1. back out the speculatively inserted tuple, then wait for the other
* transaction, and retry. Or,
* 2. wait for the other transaction, with the speculatively inserted tuple
* still in place.
*
* If two backends insert at the same time, and both try to wait for each
* other, they will deadlock. So option 2 is not acceptable. Option 1
* avoids the deadlock, but it is prone to a livelock instead. Both
* transactions will wake up immediately as the other transaction backs
* out. Then they both retry, and conflict with each other again, lather,
* rinse, repeat.
*
* To avoid the livelock, one of the backends must back out first, and then
* wait, while the other one waits without backing out. It doesn't matter
* which one backs out, so we employ an arbitrary rule that the transaction
* with the higher XID backs out.
*
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
*
Update copyright for 2023 Backpatch-through: 11
2023-01-02 21:00:37 +01:00
* Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/backend/executor/execIndexing.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
Revert "Rename files and headers related to index AM" This follows multiple complains from Peter Geoghegan, Andres Freund and Alvaro Herrera that this issue ought to be dug more before actually happening, if it happens. Discussion: https://postgr.es/m/20191226144606.GA5659@alvherre.pgsql
2019-12-27 00:09:00 +01:00
#include "access/genam.h"
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
#include "access/relscan.h"
tableam: Add and use scan APIs. Too allow table accesses to be not directly dependent on heap, several new abstractions are needed. Specifically: 1) Heap scans need to be generalized into table scans. Do this by introducing TableScanDesc, which will be the "base class" for individual AMs. This contains the AM independent fields from HeapScanDesc. The previous heap_{beginscan,rescan,endscan} et al. have been replaced with a table_ version. There's no direct replacement for heap_getnext(), as that returned a HeapTuple, which is undesirable for a other AMs. Instead there's table_scan_getnextslot(). But note that heap_getnext() lives on, it's still used widely to access catalog tables. This is achieved by new scan_begin, scan_end, scan_rescan, scan_getnextslot callbacks. 2) The portion of parallel scans that's shared between backends need to be able to do so without the user doing per-AM work. To achieve that new parallelscan_{estimate, initialize, reinitialize} callbacks are introduced, which operate on a new ParallelTableScanDesc, which again can be subclassed by AMs. As it is likely that several AMs are going to be block oriented, block oriented callbacks that can be shared between such AMs are provided and used by heap. table_block_parallelscan_{estimate, intiialize, reinitialize} as callbacks, and table_block_parallelscan_{nextpage, init} for use in AMs. These operate on a ParallelBlockTableScanDesc. 3) Index scans need to be able to access tables to return a tuple, and there needs to be state across individual accesses to the heap to store state like buffers. That's now handled by introducing a sort-of-scan IndexFetchTable, which again is intended to be subclassed by individual AMs (for heap IndexFetchHeap). The relevant callbacks for an AM are index_fetch_{end, begin, reset} to create the necessary state, and index_fetch_tuple to retrieve an indexed tuple. Note that index_fetch_tuple implementations need to be smarter than just blindly fetching the tuples for AMs that have optimizations similar to heap's HOT - the currently alive tuple in the update chain needs to be fetched if appropriate. Similar to table_scan_getnextslot(), it's undesirable to continue to return HeapTuples. Thus index_fetch_heap (might want to rename that later) now accepts a slot as an argument. Core code doesn't have a lot of call sites performing index scans without going through the systable_* API (in contrast to loads of heap_getnext calls and working directly with HeapTuples). Index scans now store the result of a search in IndexScanDesc->xs_heaptid, rather than xs_ctup->t_self. As the target is not generally a HeapTuple anymore that seems cleaner. To be able to sensible adapt code to use the above, two further callbacks have been introduced: a) slot_callbacks returns a TupleTableSlotOps* suitable for creating slots capable of holding a tuple of the AMs type. table_slot_callbacks() and table_slot_create() are based upon that, but have additional logic to deal with views, foreign tables, etc. While this change could have been done separately, nearly all the call sites that needed to be adapted for the rest of this commit also would have been needed to be adapted for table_slot_callbacks(), making separation not worthwhile. b) tuple_satisfies_snapshot checks whether the tuple in a slot is currently visible according to a snapshot. That's required as a few places now don't have a buffer + HeapTuple around, but a slot (which in heap's case internally has that information). Additionally a few infrastructure changes were needed: I) SysScanDesc, as used by systable_{beginscan, getnext} et al. now internally uses a slot to keep track of tuples. While systable_getnext() still returns HeapTuples, and will so for the foreseeable future, the index API (see 1) above) now only deals with slots. The remainder, and largest part, of this commit is then adjusting all scans in postgres to use the new APIs. Author: Andres Freund, Haribabu Kommi, Alvaro Herrera Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de https://postgr.es/m/20160812231527.GA690404@alvherre.pgsql
2019-03-11 20:46:41 +01:00
#include "access/tableam.h"
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
#include "access/xact.h"
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
#include "catalog/index.h"
#include "executor/executor.h"
#include "nodes/nodeFuncs.h"
#include "storage/lmgr.h"
Move generic snapshot related code from tqual.h to snapmgr.h. The code in tqual.c is largely heap specific. Due to the upcoming pluggable storage work, it therefore makes sense to move it into access/heap/ (as the file's header notes, the tqual name isn't very good). But the various statically allocated snapshot and snapshot initialization functions are now (see previous commit) generic and do not depend on functions declared in tqual.h anymore. Therefore move. Also move XidInMVCCSnapshot as that's useful for future AMs, and already used outside of tqual.c. Author: Andres Freund Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de
2019-01-22 02:03:15 +01:00
#include "utils/snapmgr.h"
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
/* waitMode argument to check_exclusion_or_unique_constraint() */
typedef enum
{
CEOUC_WAIT,
CEOUC_NOWAIT,
Remove trailing commas in enums. These aren't valid C89. Found thanks to gcc's -Wc90-c99-compat. These exist in differing places in most supported branches.
2016-04-15 03:54:06 +02:00
CEOUC_LIVELOCK_PREVENTING_WAIT
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
} CEOUC_WAIT_MODE;
static bool check_exclusion_or_unique_constraint(Relation heap, Relation index,
IndexInfo *indexInfo,
ItemPointer tupleid,
Datum *values, bool *isnull,
EState *estate, bool newIndex,
CEOUC_WAIT_MODE waitMode,
Harmonize parameter names in storage and AM code. Make sure that function declarations use names that exactly match the corresponding names from function definitions in storage, catalog, access method, executor, and logical replication code, as well as in miscellaneous utility/library code. Like other recent commits that cleaned up function parameter names, this commit was written with help from clang-tidy. Later commits will do the same for other parts of the codebase. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: David Rowley <dgrowleyml@gmail.com> Discussion: https://postgr.es/m/CAH2-WznJt9CMM9KJTMjJh_zbL5hD9oX44qdJ4aqZtjFi-zA3Tg@mail.gmail.com
2022-09-20 04:18:36 +02:00
bool violationOK,
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
ItemPointer conflictTid);
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
static bool index_recheck_constraint(Relation index, Oid *constr_procs,
Datum *existing_values, bool *existing_isnull,
Datum *new_values);
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
static bool index_unchanged_by_update(ResultRelInfo *resultRelInfo,
EState *estate, IndexInfo *indexInfo,
Relation indexRelation);
static bool index_expression_changed_walker(Node *node,
Bitmapset *allUpdatedCols);
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
/* ----------------------------------------------------------------
* ExecOpenIndices
*
* Find the indices associated with a result relation, open them,
* and save information about them in the result ResultRelInfo.
*
* At entry, caller has already opened and locked
* resultRelInfo->ri_RelationDesc.
* ----------------------------------------------------------------
*/
void
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
ExecOpenIndices(ResultRelInfo *resultRelInfo, bool speculative)
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
{
Relation resultRelation = resultRelInfo->ri_RelationDesc;
List *indexoidlist;
ListCell *l;
int len,
i;
RelationPtr relationDescs;
IndexInfo **indexInfoArray;
resultRelInfo->ri_NumIndices = 0;
/* fast path if no indexes */
if (!RelationGetForm(resultRelation)->relhasindex)
return;
/*
* Get cached list of index OIDs
*/
indexoidlist = RelationGetIndexList(resultRelation);
len = list_length(indexoidlist);
if (len == 0)
return;
/*
* allocate space for result arrays
*/
relationDescs = (RelationPtr) palloc(len * sizeof(Relation));
indexInfoArray = (IndexInfo **) palloc(len * sizeof(IndexInfo *));
resultRelInfo->ri_NumIndices = len;
resultRelInfo->ri_IndexRelationDescs = relationDescs;
resultRelInfo->ri_IndexRelationInfo = indexInfoArray;
/*
* For each index, open the index relation and save pg_index info. We
* acquire RowExclusiveLock, signifying we will update the index.
*
Remove obsolete IndexIs* macros Remove IndexIsValid(), IndexIsReady(), IndexIsLive() in favor of accessing the index structure directly. These macros haven't been used consistently, and the original reason of maintaining source compatibility with PostgreSQL 9.2 is gone. Discussion: https://www.postgresql.org/message-id/flat/d419147c-09d4-6196-5d9d-0234b230880a%402ndquadrant.com
2018-12-27 10:07:46 +01:00
* Note: we do this even if the index is not indisready; it's not worth
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
* the trouble to optimize for the case where it isn't.
*/
i = 0;
foreach(l, indexoidlist)
{
Oid indexOid = lfirst_oid(l);
Relation indexDesc;
IndexInfo *ii;
indexDesc = index_open(indexOid, RowExclusiveLock);
/* extract index key information from the index's pg_index info */
ii = BuildIndexInfo(indexDesc);
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
/*
* If the indexes are to be used for speculative insertion, add extra
* information required by unique index entries.
*/
if (speculative && ii->ii_Unique)
BuildSpeculativeIndexInfo(indexDesc, ii);
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
relationDescs[i] = indexDesc;
indexInfoArray[i] = ii;
i++;
}
list_free(indexoidlist);
}
/* ----------------------------------------------------------------
* ExecCloseIndices
*
* Close the index relations stored in resultRelInfo
* ----------------------------------------------------------------
*/
void
ExecCloseIndices(ResultRelInfo *resultRelInfo)
{
int i;
int numIndices;
RelationPtr indexDescs;
numIndices = resultRelInfo->ri_NumIndices;
indexDescs = resultRelInfo->ri_IndexRelationDescs;
for (i = 0; i < numIndices; i++)
{
if (indexDescs[i] == NULL)
continue; /* shouldn't happen? */
/* Drop lock acquired by ExecOpenIndices */
index_close(indexDescs[i], RowExclusiveLock);
}
/*
* XXX should free indexInfo array here too? Currently we assume that
* such stuff will be cleaned up automatically in FreeExecutorState.
*/
}
/* ----------------------------------------------------------------
* ExecInsertIndexTuples
*
* This routine takes care of inserting index tuples
* into all the relations indexing the result relation
* when a heap tuple is inserted into the result relation.
*
Ignore BRIN indexes when checking for HOT updates When determining whether an index update may be skipped by using HOT, we can ignore attributes indexed by block summarizing indexes without references to individual tuples that need to be cleaned up. A new type TU_UpdateIndexes provides a signal to the executor to determine which indexes to update - no indexes, all indexes, or only the summarizing indexes. This also removes rd_indexattr list, and replaces it with rd_attrsvalid flag. The list was not used anywhere, and a simple flag is sufficient. This was originally committed as 5753d4ee32, but then got reverted by e3fcca0d0d because of correctness issues. Original patch by Josef Simanek, various fixes and improvements by Tomas Vondra and me. Authors: Matthias van de Meent, Josef Simanek, Tomas Vondra Reviewed-by: Tomas Vondra, Alvaro Herrera Discussion: https://postgr.es/m/05ebcb44-f383-86e3-4f31-0a97a55634cf@enterprisedb.com Discussion: https://postgr.es/m/CAFp7QwpMRGcDAQumN7onN9HjrJ3u4X3ZRXdGFT0K5G2JWvnbWg%40mail.gmail.com
2023-03-20 10:34:07 +01:00
* When 'update' is true and 'onlySummarizing' is false,
* executor is performing an UPDATE that could not use an
* optimization like heapam's HOT (in more general terms a
* call to table_tuple_update() took place and set
* 'update_indexes' to TUUI_All). Receiving this hint makes
* us consider if we should pass down the 'indexUnchanged'
* hint in turn. That's something that we figure out for
* each index_insert() call iff 'update' is true.
* (When 'update' is false we already know not to pass the
* hint to any index.)
*
* If onlySummarizing is set, an equivalent optimization to
* HOT has been applied and any updated columns are indexed
* only by summarizing indexes (or in more general terms a
* call to table_tuple_update() took place and set
* 'update_indexes' to TUUI_Summarizing). We can (and must)
* therefore only update the indexes that have
* 'amsummarizing' = true.
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
*
Add comments explaining how unique and exclusion constraints are enforced.
2015-04-24 20:12:32 +02:00
* Unique and exclusion constraints are enforced at the same
* time. This returns a list of index OIDs for any unique or
* exclusion constraints that are deferred and that had
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* potential (unconfirmed) conflicts. (if noDupErr == true,
* the same is done for non-deferred constraints, but report
* if conflict was speculative or deferred conflict to caller)
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
*
Fix failure to handle conflicts in non-arbiter exclusion constraints. ExecInsertIndexTuples treated an exclusion constraint as subject to noDupErr processing even when it was not listed in arbiterIndexes, and would therefore not error out for a conflict in such a constraint, instead returning it as an arbiter-index failure. That led to an infinite loop in ExecInsert, since ExecCheckIndexConstraints ignored the index as-intended and therefore didn't throw the expected error. To fix, make the exclusion constraint code path use the same condition as the index_insert call does to decide whether no-error-for-duplicates behavior is appropriate. While at it, refactor a little bit to avoid unnecessary list_member_oid calls. (That surely wouldn't save anything worth noticing, but I find the code a bit clearer this way.) Per bug report from Heikki Rauhala. Back-patch to 9.5 where ON CONFLICT was introduced. Report: <4C976D6B-76B4-434C-8052-D009F7B7AEDA@reaktor.fi>
2016-07-04 22:09:11 +02:00
* If 'arbiterIndexes' is nonempty, noDupErr applies only to
* those indexes. NIL means noDupErr applies to all indexes.
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
* ----------------------------------------------------------------
*/
List *
Remove es_result_relation_info from EState. Maintaining 'es_result_relation_info' correctly at all times has become cumbersome, especially with partitioning where each partition gets its own result relation info. Having to set and reset it across arbitrary operations has caused bugs in the past. This changes all the places that used 'es_result_relation_info', to receive the currently active ResultRelInfo via function parameters instead. Author: Amit Langote Discussion: https://www.postgresql.org/message-id/CA%2BHiwqGEmiib8FLiHMhKB%2BCH5dRgHSLc5N5wnvc4kym%2BZYpQEQ%40mail.gmail.com
2020-10-14 10:41:40 +02:00
ExecInsertIndexTuples(ResultRelInfo *resultRelInfo,
TupleTableSlot *slot,
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
EState *estate,
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
bool update,
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
bool noDupErr,
bool *specConflict,
Ignore BRIN indexes when checking for HOT updates When determining whether an index update may be skipped by using HOT, we can ignore attributes indexed by block summarizing indexes without references to individual tuples that need to be cleaned up. A new type TU_UpdateIndexes provides a signal to the executor to determine which indexes to update - no indexes, all indexes, or only the summarizing indexes. This also removes rd_indexattr list, and replaces it with rd_attrsvalid flag. The list was not used anywhere, and a simple flag is sufficient. This was originally committed as 5753d4ee32, but then got reverted by e3fcca0d0d because of correctness issues. Original patch by Josef Simanek, various fixes and improvements by Tomas Vondra and me. Authors: Matthias van de Meent, Josef Simanek, Tomas Vondra Reviewed-by: Tomas Vondra, Alvaro Herrera Discussion: https://postgr.es/m/05ebcb44-f383-86e3-4f31-0a97a55634cf@enterprisedb.com Discussion: https://postgr.es/m/CAFp7QwpMRGcDAQumN7onN9HjrJ3u4X3ZRXdGFT0K5G2JWvnbWg%40mail.gmail.com
2023-03-20 10:34:07 +01:00
List *arbiterIndexes,
bool onlySummarizing)
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
{
tableam: Add tuple_{insert, delete, update, lock} and use. This adds new, required, table AM callbacks for insert/delete/update and lock_tuple. To be able to reasonably use those, the EvalPlanQual mechanism had to be adapted, moving more logic into the AM. Previously both delete/update/lock call-sites and the EPQ mechanism had to have awareness of the specific tuple format to be able to fetch the latest version of a tuple. Obviously that needs to be abstracted away. To do so, move the logic that find the latest row version into the AM. lock_tuple has a new flag argument, TUPLE_LOCK_FLAG_FIND_LAST_VERSION, that forces it to lock the last version, rather than the current one. It'd have been possible to do so via a separate callback as well, but finding the last version usually also necessitates locking the newest version, making it sensible to combine the two. This replaces the previous use of EvalPlanQualFetch(). Additionally HeapTupleUpdated, which previously signaled either a concurrent update or delete, is now split into two, to avoid callers needing AM specific knowledge to differentiate. The move of finding the latest row version into tuple_lock means that encountering a row concurrently moved into another partition will now raise an error about "tuple to be locked" rather than "tuple to be updated/deleted" - which is accurate, as that always happens when locking rows. While possible slightly less helpful for users, it seems like an acceptable trade-off. As part of this commit HTSU_Result has been renamed to TM_Result, and its members been expanded to differentiated between updating and deleting. HeapUpdateFailureData has been renamed to TM_FailureData. The interface to speculative insertion is changed so nodeModifyTable.c does not have to set the speculative token itself anymore. Instead there's a version of tuple_insert, tuple_insert_speculative, that performs the speculative insertion (without requiring a flag to signal that fact), and the speculative insertion is either made permanent with table_complete_speculative(succeeded = true) or aborted with succeeded = false). Note that multi_insert is not yet routed through tableam, nor is COPY. Changing multi_insert requires changes to copy.c that are large enough to better be done separately. Similarly, although simpler, CREATE TABLE AS and CREATE MATERIALIZED VIEW are also only going to be adjusted in a later commit. Author: Andres Freund and Haribabu Kommi Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de https://postgr.es/m/20190313003903.nwvrxi7rw3ywhdel@alap3.anarazel.de https://postgr.es/m/20160812231527.GA690404@alvherre.pgsql
2019-03-24 03:55:57 +01:00
ItemPointer tupleid = &slot->tts_tid;
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
List *result = NIL;
int i;
int numIndices;
RelationPtr relationDescs;
Relation heapRelation;
IndexInfo **indexInfoArray;
ExprContext *econtext;
Datum values[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
tableam: Add tuple_{insert, delete, update, lock} and use. This adds new, required, table AM callbacks for insert/delete/update and lock_tuple. To be able to reasonably use those, the EvalPlanQual mechanism had to be adapted, moving more logic into the AM. Previously both delete/update/lock call-sites and the EPQ mechanism had to have awareness of the specific tuple format to be able to fetch the latest version of a tuple. Obviously that needs to be abstracted away. To do so, move the logic that find the latest row version into the AM. lock_tuple has a new flag argument, TUPLE_LOCK_FLAG_FIND_LAST_VERSION, that forces it to lock the last version, rather than the current one. It'd have been possible to do so via a separate callback as well, but finding the last version usually also necessitates locking the newest version, making it sensible to combine the two. This replaces the previous use of EvalPlanQualFetch(). Additionally HeapTupleUpdated, which previously signaled either a concurrent update or delete, is now split into two, to avoid callers needing AM specific knowledge to differentiate. The move of finding the latest row version into tuple_lock means that encountering a row concurrently moved into another partition will now raise an error about "tuple to be locked" rather than "tuple to be updated/deleted" - which is accurate, as that always happens when locking rows. While possible slightly less helpful for users, it seems like an acceptable trade-off. As part of this commit HTSU_Result has been renamed to TM_Result, and its members been expanded to differentiated between updating and deleting. HeapUpdateFailureData has been renamed to TM_FailureData. The interface to speculative insertion is changed so nodeModifyTable.c does not have to set the speculative token itself anymore. Instead there's a version of tuple_insert, tuple_insert_speculative, that performs the speculative insertion (without requiring a flag to signal that fact), and the speculative insertion is either made permanent with table_complete_speculative(succeeded = true) or aborted with succeeded = false). Note that multi_insert is not yet routed through tableam, nor is COPY. Changing multi_insert requires changes to copy.c that are large enough to better be done separately. Similarly, although simpler, CREATE TABLE AS and CREATE MATERIALIZED VIEW are also only going to be adjusted in a later commit. Author: Andres Freund and Haribabu Kommi Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de https://postgr.es/m/20190313003903.nwvrxi7rw3ywhdel@alap3.anarazel.de https://postgr.es/m/20160812231527.GA690404@alvherre.pgsql
2019-03-24 03:55:57 +01:00
Assert(ItemPointerIsValid(tupleid));
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
/*
* Get information from the result relation info structure.
*/
numIndices = resultRelInfo->ri_NumIndices;
relationDescs = resultRelInfo->ri_IndexRelationDescs;
indexInfoArray = resultRelInfo->ri_IndexRelationInfo;
heapRelation = resultRelInfo->ri_RelationDesc;
Fix incorrect index behavior in COPY FROM with partitioned tables 86b85044e rewrote how COPY FROM works to allow multiple tuple buffers to exist to once thus allowing multi-inserts to be used in more cases with partitioned tables. That commit neglected to update the estate's es_result_relation_info when flushing the insert buffer to the partition making it possible for the index tuples to be added into an index on the wrong partition. Fix this and also add an Assert in ExecInsertIndexTuples to help ensure that we never make this mistake again. Reported-by: Haruka Takatsuka Author: Ashutosh Sharma Discussion: https://postgr.es/m/15832-b1bf336a4ee246b5@postgresql.org
2019-06-05 08:28:38 +02:00
/* Sanity check: slot must belong to the same rel as the resultRelInfo. */
Assert(slot->tts_tableOid == RelationGetRelid(heapRelation));
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
/*
* We will use the EState's per-tuple context for evaluating predicates
* and index expressions (creating it if it's not already there).
*/
econtext = GetPerTupleExprContext(estate);
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/*
* for each index, form and insert the index tuple
*/
for (i = 0; i < numIndices; i++)
{
Relation indexRelation = relationDescs[i];
IndexInfo *indexInfo;
Fix failure to handle conflicts in non-arbiter exclusion constraints. ExecInsertIndexTuples treated an exclusion constraint as subject to noDupErr processing even when it was not listed in arbiterIndexes, and would therefore not error out for a conflict in such a constraint, instead returning it as an arbiter-index failure. That led to an infinite loop in ExecInsert, since ExecCheckIndexConstraints ignored the index as-intended and therefore didn't throw the expected error. To fix, make the exclusion constraint code path use the same condition as the index_insert call does to decide whether no-error-for-duplicates behavior is appropriate. While at it, refactor a little bit to avoid unnecessary list_member_oid calls. (That surely wouldn't save anything worth noticing, but I find the code a bit clearer this way.) Per bug report from Heikki Rauhala. Back-patch to 9.5 where ON CONFLICT was introduced. Report: <4C976D6B-76B4-434C-8052-D009F7B7AEDA@reaktor.fi>
2016-07-04 22:09:11 +02:00
bool applyNoDupErr;
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
IndexUniqueCheck checkUnique;
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
bool indexUnchanged;
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
bool satisfiesConstraint;
if (indexRelation == NULL)
continue;
indexInfo = indexInfoArray[i];
/* If the index is marked as read-only, ignore it */
if (!indexInfo->ii_ReadyForInserts)
continue;
Ignore BRIN indexes when checking for HOT updates When determining whether an index update may be skipped by using HOT, we can ignore attributes indexed by block summarizing indexes without references to individual tuples that need to be cleaned up. A new type TU_UpdateIndexes provides a signal to the executor to determine which indexes to update - no indexes, all indexes, or only the summarizing indexes. This also removes rd_indexattr list, and replaces it with rd_attrsvalid flag. The list was not used anywhere, and a simple flag is sufficient. This was originally committed as 5753d4ee32, but then got reverted by e3fcca0d0d because of correctness issues. Original patch by Josef Simanek, various fixes and improvements by Tomas Vondra and me. Authors: Matthias van de Meent, Josef Simanek, Tomas Vondra Reviewed-by: Tomas Vondra, Alvaro Herrera Discussion: https://postgr.es/m/05ebcb44-f383-86e3-4f31-0a97a55634cf@enterprisedb.com Discussion: https://postgr.es/m/CAFp7QwpMRGcDAQumN7onN9HjrJ3u4X3ZRXdGFT0K5G2JWvnbWg%40mail.gmail.com
2023-03-20 10:34:07 +01:00
/*
Pre-beta mechanical code beautification. Run pgindent, pgperltidy, and reformat-dat-files. This set of diffs is a bit larger than typical. We've updated to pg_bsd_indent 2.1.2, which properly indents variable declarations that have multi-line initialization expressions (the continuation lines are now indented one tab stop). We've also updated to perltidy version 20230309 and changed some of its settings, which reduces its desire to add whitespace to lines to make assignments etc. line up. Going forward, that should make for fewer random-seeming changes to existing code. Discussion: https://postgr.es/m/20230428092545.qfb3y5wcu4cm75ur@alvherre.pgsql
2023-05-19 23:24:48 +02:00
* Skip processing of non-summarizing indexes if we only update
* summarizing indexes
Ignore BRIN indexes when checking for HOT updates When determining whether an index update may be skipped by using HOT, we can ignore attributes indexed by block summarizing indexes without references to individual tuples that need to be cleaned up. A new type TU_UpdateIndexes provides a signal to the executor to determine which indexes to update - no indexes, all indexes, or only the summarizing indexes. This also removes rd_indexattr list, and replaces it with rd_attrsvalid flag. The list was not used anywhere, and a simple flag is sufficient. This was originally committed as 5753d4ee32, but then got reverted by e3fcca0d0d because of correctness issues. Original patch by Josef Simanek, various fixes and improvements by Tomas Vondra and me. Authors: Matthias van de Meent, Josef Simanek, Tomas Vondra Reviewed-by: Tomas Vondra, Alvaro Herrera Discussion: https://postgr.es/m/05ebcb44-f383-86e3-4f31-0a97a55634cf@enterprisedb.com Discussion: https://postgr.es/m/CAFp7QwpMRGcDAQumN7onN9HjrJ3u4X3ZRXdGFT0K5G2JWvnbWg%40mail.gmail.com
2023-03-20 10:34:07 +01:00
*/
if (onlySummarizing && !indexInfo->ii_Summarizing)
continue;
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
/* Check for partial index */
if (indexInfo->ii_Predicate != NIL)
{
Faster expression evaluation and targetlist projection. This replaces the old, recursive tree-walk based evaluation, with non-recursive, opcode dispatch based, expression evaluation. Projection is now implemented as part of expression evaluation. This both leads to significant performance improvements, and makes future just-in-time compilation of expressions easier. The speed gains primarily come from: - non-recursive implementation reduces stack usage / overhead - simple sub-expressions are implemented with a single jump, without function calls - sharing some state between different sub-expressions - reduced amount of indirect/hard to predict memory accesses by laying out operation metadata sequentially; including the avoidance of nearly all of the previously used linked lists - more code has been moved to expression initialization, avoiding constant re-checks at evaluation time Future just-in-time compilation (JIT) has become easier, as demonstrated by released patches intended to be merged in a later release, for primarily two reasons: Firstly, due to a stricter split between expression initialization and evaluation, less code has to be handled by the JIT. Secondly, due to the non-recursive nature of the generated "instructions", less performance-critical code-paths can easily be shared between interpreted and compiled evaluation. The new framework allows for significant future optimizations. E.g.: - basic infrastructure for to later reduce the per executor-startup overhead of expression evaluation, by caching state in prepared statements. That'd be helpful in OLTPish scenarios where initialization overhead is measurable. - optimizing the generated "code". A number of proposals for potential work has already been made. - optimizing the interpreter. Similarly a number of proposals have been made here too. The move of logic into the expression initialization step leads to some backward-incompatible changes: - Function permission checks are now done during expression initialization, whereas previously they were done during execution. In edge cases this can lead to errors being raised that previously wouldn't have been, e.g. a NULL array being coerced to a different array type previously didn't perform checks. - The set of domain constraints to be checked, is now evaluated once during expression initialization, previously it was re-built every time a domain check was evaluated. For normal queries this doesn't change much, but e.g. for plpgsql functions, which caches ExprStates, the old set could stick around longer. The behavior around might still change. Author: Andres Freund, with significant changes by Tom Lane, changes by Heikki Linnakangas Reviewed-By: Tom Lane, Heikki Linnakangas Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
ExprState *predicate;
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
/*
* If predicate state not set up yet, create it (in the estate's
* per-query context)
*/
predicate = indexInfo->ii_PredicateState;
Faster expression evaluation and targetlist projection. This replaces the old, recursive tree-walk based evaluation, with non-recursive, opcode dispatch based, expression evaluation. Projection is now implemented as part of expression evaluation. This both leads to significant performance improvements, and makes future just-in-time compilation of expressions easier. The speed gains primarily come from: - non-recursive implementation reduces stack usage / overhead - simple sub-expressions are implemented with a single jump, without function calls - sharing some state between different sub-expressions - reduced amount of indirect/hard to predict memory accesses by laying out operation metadata sequentially; including the avoidance of nearly all of the previously used linked lists - more code has been moved to expression initialization, avoiding constant re-checks at evaluation time Future just-in-time compilation (JIT) has become easier, as demonstrated by released patches intended to be merged in a later release, for primarily two reasons: Firstly, due to a stricter split between expression initialization and evaluation, less code has to be handled by the JIT. Secondly, due to the non-recursive nature of the generated "instructions", less performance-critical code-paths can easily be shared between interpreted and compiled evaluation. The new framework allows for significant future optimizations. E.g.: - basic infrastructure for to later reduce the per executor-startup overhead of expression evaluation, by caching state in prepared statements. That'd be helpful in OLTPish scenarios where initialization overhead is measurable. - optimizing the generated "code". A number of proposals for potential work has already been made. - optimizing the interpreter. Similarly a number of proposals have been made here too. The move of logic into the expression initialization step leads to some backward-incompatible changes: - Function permission checks are now done during expression initialization, whereas previously they were done during execution. In edge cases this can lead to errors being raised that previously wouldn't have been, e.g. a NULL array being coerced to a different array type previously didn't perform checks. - The set of domain constraints to be checked, is now evaluated once during expression initialization, previously it was re-built every time a domain check was evaluated. For normal queries this doesn't change much, but e.g. for plpgsql functions, which caches ExprStates, the old set could stick around longer. The behavior around might still change. Author: Andres Freund, with significant changes by Tom Lane, changes by Heikki Linnakangas Reviewed-By: Tom Lane, Heikki Linnakangas Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
if (predicate == NULL)
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
{
Faster expression evaluation and targetlist projection. This replaces the old, recursive tree-walk based evaluation, with non-recursive, opcode dispatch based, expression evaluation. Projection is now implemented as part of expression evaluation. This both leads to significant performance improvements, and makes future just-in-time compilation of expressions easier. The speed gains primarily come from: - non-recursive implementation reduces stack usage / overhead - simple sub-expressions are implemented with a single jump, without function calls - sharing some state between different sub-expressions - reduced amount of indirect/hard to predict memory accesses by laying out operation metadata sequentially; including the avoidance of nearly all of the previously used linked lists - more code has been moved to expression initialization, avoiding constant re-checks at evaluation time Future just-in-time compilation (JIT) has become easier, as demonstrated by released patches intended to be merged in a later release, for primarily two reasons: Firstly, due to a stricter split between expression initialization and evaluation, less code has to be handled by the JIT. Secondly, due to the non-recursive nature of the generated "instructions", less performance-critical code-paths can easily be shared between interpreted and compiled evaluation. The new framework allows for significant future optimizations. E.g.: - basic infrastructure for to later reduce the per executor-startup overhead of expression evaluation, by caching state in prepared statements. That'd be helpful in OLTPish scenarios where initialization overhead is measurable. - optimizing the generated "code". A number of proposals for potential work has already been made. - optimizing the interpreter. Similarly a number of proposals have been made here too. The move of logic into the expression initialization step leads to some backward-incompatible changes: - Function permission checks are now done during expression initialization, whereas previously they were done during execution. In edge cases this can lead to errors being raised that previously wouldn't have been, e.g. a NULL array being coerced to a different array type previously didn't perform checks. - The set of domain constraints to be checked, is now evaluated once during expression initialization, previously it was re-built every time a domain check was evaluated. For normal queries this doesn't change much, but e.g. for plpgsql functions, which caches ExprStates, the old set could stick around longer. The behavior around might still change. Author: Andres Freund, with significant changes by Tom Lane, changes by Heikki Linnakangas Reviewed-By: Tom Lane, Heikki Linnakangas Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
predicate = ExecPrepareQual(indexInfo->ii_Predicate, estate);
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
indexInfo->ii_PredicateState = predicate;
}
/* Skip this index-update if the predicate isn't satisfied */
Faster expression evaluation and targetlist projection. This replaces the old, recursive tree-walk based evaluation, with non-recursive, opcode dispatch based, expression evaluation. Projection is now implemented as part of expression evaluation. This both leads to significant performance improvements, and makes future just-in-time compilation of expressions easier. The speed gains primarily come from: - non-recursive implementation reduces stack usage / overhead - simple sub-expressions are implemented with a single jump, without function calls - sharing some state between different sub-expressions - reduced amount of indirect/hard to predict memory accesses by laying out operation metadata sequentially; including the avoidance of nearly all of the previously used linked lists - more code has been moved to expression initialization, avoiding constant re-checks at evaluation time Future just-in-time compilation (JIT) has become easier, as demonstrated by released patches intended to be merged in a later release, for primarily two reasons: Firstly, due to a stricter split between expression initialization and evaluation, less code has to be handled by the JIT. Secondly, due to the non-recursive nature of the generated "instructions", less performance-critical code-paths can easily be shared between interpreted and compiled evaluation. The new framework allows for significant future optimizations. E.g.: - basic infrastructure for to later reduce the per executor-startup overhead of expression evaluation, by caching state in prepared statements. That'd be helpful in OLTPish scenarios where initialization overhead is measurable. - optimizing the generated "code". A number of proposals for potential work has already been made. - optimizing the interpreter. Similarly a number of proposals have been made here too. The move of logic into the expression initialization step leads to some backward-incompatible changes: - Function permission checks are now done during expression initialization, whereas previously they were done during execution. In edge cases this can lead to errors being raised that previously wouldn't have been, e.g. a NULL array being coerced to a different array type previously didn't perform checks. - The set of domain constraints to be checked, is now evaluated once during expression initialization, previously it was re-built every time a domain check was evaluated. For normal queries this doesn't change much, but e.g. for plpgsql functions, which caches ExprStates, the old set could stick around longer. The behavior around might still change. Author: Andres Freund, with significant changes by Tom Lane, changes by Heikki Linnakangas Reviewed-By: Tom Lane, Heikki Linnakangas Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
if (!ExecQual(predicate, econtext))
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
continue;
}
/*
* FormIndexDatum fills in its values and isnull parameters with the
* appropriate values for the column(s) of the index.
*/
FormIndexDatum(indexInfo,
slot,
estate,
values,
isnull);
Fix failure to handle conflicts in non-arbiter exclusion constraints. ExecInsertIndexTuples treated an exclusion constraint as subject to noDupErr processing even when it was not listed in arbiterIndexes, and would therefore not error out for a conflict in such a constraint, instead returning it as an arbiter-index failure. That led to an infinite loop in ExecInsert, since ExecCheckIndexConstraints ignored the index as-intended and therefore didn't throw the expected error. To fix, make the exclusion constraint code path use the same condition as the index_insert call does to decide whether no-error-for-duplicates behavior is appropriate. While at it, refactor a little bit to avoid unnecessary list_member_oid calls. (That surely wouldn't save anything worth noticing, but I find the code a bit clearer this way.) Per bug report from Heikki Rauhala. Back-patch to 9.5 where ON CONFLICT was introduced. Report: <4C976D6B-76B4-434C-8052-D009F7B7AEDA@reaktor.fi>
2016-07-04 22:09:11 +02:00
/* Check whether to apply noDupErr to this index */
applyNoDupErr = noDupErr &&
(arbiterIndexes == NIL ||
list_member_oid(arbiterIndexes,
indexRelation->rd_index->indexrelid));
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
/*
* The index AM does the actual insertion, plus uniqueness checking.
*
* For an immediate-mode unique index, we just tell the index AM to
* throw error if not unique.
*
* For a deferrable unique index, we tell the index AM to just detect
* possible non-uniqueness, and we add the index OID to the result
* list if further checking is needed.
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
*
* For a speculative insertion (used by INSERT ... ON CONFLICT), do
* the same as for a deferrable unique index.
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
*/
if (!indexRelation->rd_index->indisunique)
checkUnique = UNIQUE_CHECK_NO;
Fix failure to handle conflicts in non-arbiter exclusion constraints. ExecInsertIndexTuples treated an exclusion constraint as subject to noDupErr processing even when it was not listed in arbiterIndexes, and would therefore not error out for a conflict in such a constraint, instead returning it as an arbiter-index failure. That led to an infinite loop in ExecInsert, since ExecCheckIndexConstraints ignored the index as-intended and therefore didn't throw the expected error. To fix, make the exclusion constraint code path use the same condition as the index_insert call does to decide whether no-error-for-duplicates behavior is appropriate. While at it, refactor a little bit to avoid unnecessary list_member_oid calls. (That surely wouldn't save anything worth noticing, but I find the code a bit clearer this way.) Per bug report from Heikki Rauhala. Back-patch to 9.5 where ON CONFLICT was introduced. Report: <4C976D6B-76B4-434C-8052-D009F7B7AEDA@reaktor.fi>
2016-07-04 22:09:11 +02:00
else if (applyNoDupErr)
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
checkUnique = UNIQUE_CHECK_PARTIAL;
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
else if (indexRelation->rd_index->indimmediate)
checkUnique = UNIQUE_CHECK_YES;
else
checkUnique = UNIQUE_CHECK_PARTIAL;
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
/*
* There's definitely going to be an index_insert() call for this
* index. If we're being called as part of an UPDATE statement,
* consider if the 'indexUnchanged' = true hint should be passed.
*/
indexUnchanged = update && index_unchanged_by_update(resultRelInfo,
estate,
indexInfo,
indexRelation);
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
satisfiesConstraint =
index_insert(indexRelation, /* index relation */
values, /* array of index Datums */
isnull, /* null flags */
tupleid, /* tid of heap tuple */
heapRelation, /* heap relation */
Allow index AMs to cache data across aminsert calls within a SQL command. It's always been possible for index AMs to cache data across successive amgettuple calls within a single SQL command: the IndexScanDesc.opaque field is meant for precisely that. However, no comparable facility exists for amortizing setup work across successive aminsert calls. This patch adds such a feature and teaches GIN, GIST, and BRIN to use it to amortize catalog lookups they'd previously been doing on every call. (The other standard index AMs keep everything they need in the relcache, so there's little to improve there.) For GIN, the overall improvement in a statement that inserts many rows can be as much as 10%, though it seems a bit less for the other two. In addition, this makes a really significant difference in runtime for CLOBBER_CACHE_ALWAYS tests, since in those builds the repeated catalog lookups are vastly more expensive. The reason this has been hard up to now is that the aminsert function is not passed any useful place to cache per-statement data. What I chose to do is to add suitable fields to struct IndexInfo and pass that to aminsert. That's not widening the index AM API very much because IndexInfo is already within the ken of ambuild; in fact, by passing the same info to aminsert as to ambuild, this is really removing an inconsistency in the AM API. Discussion: https://postgr.es/m/27568.1486508680@sss.pgh.pa.us
2017-02-09 17:52:12 +01:00
checkUnique, /* type of uniqueness check to do */
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
indexUnchanged, /* UPDATE without logical change? */
Allow index AMs to cache data across aminsert calls within a SQL command. It's always been possible for index AMs to cache data across successive amgettuple calls within a single SQL command: the IndexScanDesc.opaque field is meant for precisely that. However, no comparable facility exists for amortizing setup work across successive aminsert calls. This patch adds such a feature and teaches GIN, GIST, and BRIN to use it to amortize catalog lookups they'd previously been doing on every call. (The other standard index AMs keep everything they need in the relcache, so there's little to improve there.) For GIN, the overall improvement in a statement that inserts many rows can be as much as 10%, though it seems a bit less for the other two. In addition, this makes a really significant difference in runtime for CLOBBER_CACHE_ALWAYS tests, since in those builds the repeated catalog lookups are vastly more expensive. The reason this has been hard up to now is that the aminsert function is not passed any useful place to cache per-statement data. What I chose to do is to add suitable fields to struct IndexInfo and pass that to aminsert. That's not widening the index AM API very much because IndexInfo is already within the ken of ambuild; in fact, by passing the same info to aminsert as to ambuild, this is really removing an inconsistency in the AM API. Discussion: https://postgr.es/m/27568.1486508680@sss.pgh.pa.us
2017-02-09 17:52:12 +01:00
indexInfo); /* index AM may need this */
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
/*
* If the index has an associated exclusion constraint, check that.
* This is simpler than the process for uniqueness checks since we
* always insert first and then check. If the constraint is deferred,
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* we check now anyway, but don't throw error on violation or wait for
* a conclusive outcome from a concurrent insertion; instead we'll
* queue a recheck event. Similarly, noDupErr callers (speculative
* inserters) will recheck later, and wait for a conclusive outcome
* then.
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
*
* An index for an exclusion constraint can't also be UNIQUE (not an
* essential property, we just don't allow it in the grammar), so no
* need to preserve the prior state of satisfiesConstraint.
*/
if (indexInfo->ii_ExclusionOps != NULL)
{
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
bool violationOK;
Correct type of waitMode variable in ExecInsertIndexTuples(). It was a bool, even though it should be CEOUC_WAIT_MODE. That's unlikely to have a negative effect with the current definition of bool (char), but it's definitely wrong. Discussion: 20150812084351.GD8470@awork2.anarazel.de Backpatch: 9.5, where ON CONFLICT was merged
2015-08-15 17:02:47 +02:00
CEOUC_WAIT_MODE waitMode;
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
Fix failure to handle conflicts in non-arbiter exclusion constraints. ExecInsertIndexTuples treated an exclusion constraint as subject to noDupErr processing even when it was not listed in arbiterIndexes, and would therefore not error out for a conflict in such a constraint, instead returning it as an arbiter-index failure. That led to an infinite loop in ExecInsert, since ExecCheckIndexConstraints ignored the index as-intended and therefore didn't throw the expected error. To fix, make the exclusion constraint code path use the same condition as the index_insert call does to decide whether no-error-for-duplicates behavior is appropriate. While at it, refactor a little bit to avoid unnecessary list_member_oid calls. (That surely wouldn't save anything worth noticing, but I find the code a bit clearer this way.) Per bug report from Heikki Rauhala. Back-patch to 9.5 where ON CONFLICT was introduced. Report: <4C976D6B-76B4-434C-8052-D009F7B7AEDA@reaktor.fi>
2016-07-04 22:09:11 +02:00
if (applyNoDupErr)
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
{
violationOK = true;
waitMode = CEOUC_LIVELOCK_PREVENTING_WAIT;
}
else if (!indexRelation->rd_index->indimmediate)
{
violationOK = true;
waitMode = CEOUC_NOWAIT;
}
else
{
violationOK = false;
waitMode = CEOUC_WAIT;
}
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
satisfiesConstraint =
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
check_exclusion_or_unique_constraint(heapRelation,
indexRelation, indexInfo,
tupleid, values, isnull,
estate, false,
waitMode, violationOK, NULL);
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
}
if ((checkUnique == UNIQUE_CHECK_PARTIAL ||
indexInfo->ii_ExclusionOps != NULL) &&
!satisfiesConstraint)
{
/*
* The tuple potentially violates the uniqueness or exclusion
* constraint, so make a note of the index so that we can re-check
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* it later. Speculative inserters are told if there was a
* speculative conflict, since that always requires a restart.
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
*/
result = lappend_oid(result, RelationGetRelid(indexRelation));
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
if (indexRelation->rd_index->indimmediate && specConflict)
*specConflict = true;
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
}
}
return result;
}
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
/* ----------------------------------------------------------------
* ExecCheckIndexConstraints
*
* This routine checks if a tuple violates any unique or
Remove duplicate word. Amit Langote
2015-10-20 16:29:19 +02:00
* exclusion constraints. Returns true if there is no conflict.
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* Otherwise returns false, and the TID of the conflicting
* tuple is returned in *conflictTid.
*
* If 'arbiterIndexes' is given, only those indexes are checked.
* NIL means all indexes.
*
* Note that this doesn't lock the values in any way, so it's
* possible that a conflicting tuple is inserted immediately
* after this returns. But this can be used for a pre-check
* before insertion.
* ----------------------------------------------------------------
*/
bool
Remove es_result_relation_info from EState. Maintaining 'es_result_relation_info' correctly at all times has become cumbersome, especially with partitioning where each partition gets its own result relation info. Having to set and reset it across arbitrary operations has caused bugs in the past. This changes all the places that used 'es_result_relation_info', to receive the currently active ResultRelInfo via function parameters instead. Author: Amit Langote Discussion: https://www.postgresql.org/message-id/CA%2BHiwqGEmiib8FLiHMhKB%2BCH5dRgHSLc5N5wnvc4kym%2BZYpQEQ%40mail.gmail.com
2020-10-14 10:41:40 +02:00
ExecCheckIndexConstraints(ResultRelInfo *resultRelInfo, TupleTableSlot *slot,
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
EState *estate, ItemPointer conflictTid,
List *arbiterIndexes)
{
int i;
int numIndices;
RelationPtr relationDescs;
Relation heapRelation;
IndexInfo **indexInfoArray;
ExprContext *econtext;
Datum values[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
ItemPointerData invalidItemPtr;
bool checkedIndex = false;
ItemPointerSetInvalid(conflictTid);
ItemPointerSetInvalid(&invalidItemPtr);
/*
* Get information from the result relation info structure.
*/
numIndices = resultRelInfo->ri_NumIndices;
relationDescs = resultRelInfo->ri_IndexRelationDescs;
indexInfoArray = resultRelInfo->ri_IndexRelationInfo;
heapRelation = resultRelInfo->ri_RelationDesc;
/*
* We will use the EState's per-tuple context for evaluating predicates
* and index expressions (creating it if it's not already there).
*/
econtext = GetPerTupleExprContext(estate);
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/*
* For each index, form index tuple and check if it satisfies the
* constraint.
*/
for (i = 0; i < numIndices; i++)
{
Relation indexRelation = relationDescs[i];
IndexInfo *indexInfo;
bool satisfiesConstraint;
if (indexRelation == NULL)
continue;
indexInfo = indexInfoArray[i];
if (!indexInfo->ii_Unique && !indexInfo->ii_ExclusionOps)
continue;
/* If the index is marked as read-only, ignore it */
if (!indexInfo->ii_ReadyForInserts)
continue;
/* When specific arbiter indexes requested, only examine them */
if (arbiterIndexes != NIL &&
!list_member_oid(arbiterIndexes,
indexRelation->rd_index->indexrelid))
continue;
if (!indexRelation->rd_index->indimmediate)
ereport(ERROR,
Improve INSERT .. ON CONFLICT error message. Peter Geoghegan, reviewed by me.
2015-10-13 21:33:07 +02:00
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("ON CONFLICT does not support deferrable unique constraints/exclusion constraints as arbiters"),
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
errtableconstraint(heapRelation,
RelationGetRelationName(indexRelation))));
checkedIndex = true;
/* Check for partial index */
if (indexInfo->ii_Predicate != NIL)
{
Faster expression evaluation and targetlist projection. This replaces the old, recursive tree-walk based evaluation, with non-recursive, opcode dispatch based, expression evaluation. Projection is now implemented as part of expression evaluation. This both leads to significant performance improvements, and makes future just-in-time compilation of expressions easier. The speed gains primarily come from: - non-recursive implementation reduces stack usage / overhead - simple sub-expressions are implemented with a single jump, without function calls - sharing some state between different sub-expressions - reduced amount of indirect/hard to predict memory accesses by laying out operation metadata sequentially; including the avoidance of nearly all of the previously used linked lists - more code has been moved to expression initialization, avoiding constant re-checks at evaluation time Future just-in-time compilation (JIT) has become easier, as demonstrated by released patches intended to be merged in a later release, for primarily two reasons: Firstly, due to a stricter split between expression initialization and evaluation, less code has to be handled by the JIT. Secondly, due to the non-recursive nature of the generated "instructions", less performance-critical code-paths can easily be shared between interpreted and compiled evaluation. The new framework allows for significant future optimizations. E.g.: - basic infrastructure for to later reduce the per executor-startup overhead of expression evaluation, by caching state in prepared statements. That'd be helpful in OLTPish scenarios where initialization overhead is measurable. - optimizing the generated "code". A number of proposals for potential work has already been made. - optimizing the interpreter. Similarly a number of proposals have been made here too. The move of logic into the expression initialization step leads to some backward-incompatible changes: - Function permission checks are now done during expression initialization, whereas previously they were done during execution. In edge cases this can lead to errors being raised that previously wouldn't have been, e.g. a NULL array being coerced to a different array type previously didn't perform checks. - The set of domain constraints to be checked, is now evaluated once during expression initialization, previously it was re-built every time a domain check was evaluated. For normal queries this doesn't change much, but e.g. for plpgsql functions, which caches ExprStates, the old set could stick around longer. The behavior around might still change. Author: Andres Freund, with significant changes by Tom Lane, changes by Heikki Linnakangas Reviewed-By: Tom Lane, Heikki Linnakangas Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
ExprState *predicate;
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
/*
* If predicate state not set up yet, create it (in the estate's
* per-query context)
*/
predicate = indexInfo->ii_PredicateState;
Faster expression evaluation and targetlist projection. This replaces the old, recursive tree-walk based evaluation, with non-recursive, opcode dispatch based, expression evaluation. Projection is now implemented as part of expression evaluation. This both leads to significant performance improvements, and makes future just-in-time compilation of expressions easier. The speed gains primarily come from: - non-recursive implementation reduces stack usage / overhead - simple sub-expressions are implemented with a single jump, without function calls - sharing some state between different sub-expressions - reduced amount of indirect/hard to predict memory accesses by laying out operation metadata sequentially; including the avoidance of nearly all of the previously used linked lists - more code has been moved to expression initialization, avoiding constant re-checks at evaluation time Future just-in-time compilation (JIT) has become easier, as demonstrated by released patches intended to be merged in a later release, for primarily two reasons: Firstly, due to a stricter split between expression initialization and evaluation, less code has to be handled by the JIT. Secondly, due to the non-recursive nature of the generated "instructions", less performance-critical code-paths can easily be shared between interpreted and compiled evaluation. The new framework allows for significant future optimizations. E.g.: - basic infrastructure for to later reduce the per executor-startup overhead of expression evaluation, by caching state in prepared statements. That'd be helpful in OLTPish scenarios where initialization overhead is measurable. - optimizing the generated "code". A number of proposals for potential work has already been made. - optimizing the interpreter. Similarly a number of proposals have been made here too. The move of logic into the expression initialization step leads to some backward-incompatible changes: - Function permission checks are now done during expression initialization, whereas previously they were done during execution. In edge cases this can lead to errors being raised that previously wouldn't have been, e.g. a NULL array being coerced to a different array type previously didn't perform checks. - The set of domain constraints to be checked, is now evaluated once during expression initialization, previously it was re-built every time a domain check was evaluated. For normal queries this doesn't change much, but e.g. for plpgsql functions, which caches ExprStates, the old set could stick around longer. The behavior around might still change. Author: Andres Freund, with significant changes by Tom Lane, changes by Heikki Linnakangas Reviewed-By: Tom Lane, Heikki Linnakangas Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
if (predicate == NULL)
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
{
Faster expression evaluation and targetlist projection. This replaces the old, recursive tree-walk based evaluation, with non-recursive, opcode dispatch based, expression evaluation. Projection is now implemented as part of expression evaluation. This both leads to significant performance improvements, and makes future just-in-time compilation of expressions easier. The speed gains primarily come from: - non-recursive implementation reduces stack usage / overhead - simple sub-expressions are implemented with a single jump, without function calls - sharing some state between different sub-expressions - reduced amount of indirect/hard to predict memory accesses by laying out operation metadata sequentially; including the avoidance of nearly all of the previously used linked lists - more code has been moved to expression initialization, avoiding constant re-checks at evaluation time Future just-in-time compilation (JIT) has become easier, as demonstrated by released patches intended to be merged in a later release, for primarily two reasons: Firstly, due to a stricter split between expression initialization and evaluation, less code has to be handled by the JIT. Secondly, due to the non-recursive nature of the generated "instructions", less performance-critical code-paths can easily be shared between interpreted and compiled evaluation. The new framework allows for significant future optimizations. E.g.: - basic infrastructure for to later reduce the per executor-startup overhead of expression evaluation, by caching state in prepared statements. That'd be helpful in OLTPish scenarios where initialization overhead is measurable. - optimizing the generated "code". A number of proposals for potential work has already been made. - optimizing the interpreter. Similarly a number of proposals have been made here too. The move of logic into the expression initialization step leads to some backward-incompatible changes: - Function permission checks are now done during expression initialization, whereas previously they were done during execution. In edge cases this can lead to errors being raised that previously wouldn't have been, e.g. a NULL array being coerced to a different array type previously didn't perform checks. - The set of domain constraints to be checked, is now evaluated once during expression initialization, previously it was re-built every time a domain check was evaluated. For normal queries this doesn't change much, but e.g. for plpgsql functions, which caches ExprStates, the old set could stick around longer. The behavior around might still change. Author: Andres Freund, with significant changes by Tom Lane, changes by Heikki Linnakangas Reviewed-By: Tom Lane, Heikki Linnakangas Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
predicate = ExecPrepareQual(indexInfo->ii_Predicate, estate);
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
indexInfo->ii_PredicateState = predicate;
}
/* Skip this index-update if the predicate isn't satisfied */
Faster expression evaluation and targetlist projection. This replaces the old, recursive tree-walk based evaluation, with non-recursive, opcode dispatch based, expression evaluation. Projection is now implemented as part of expression evaluation. This both leads to significant performance improvements, and makes future just-in-time compilation of expressions easier. The speed gains primarily come from: - non-recursive implementation reduces stack usage / overhead - simple sub-expressions are implemented with a single jump, without function calls - sharing some state between different sub-expressions - reduced amount of indirect/hard to predict memory accesses by laying out operation metadata sequentially; including the avoidance of nearly all of the previously used linked lists - more code has been moved to expression initialization, avoiding constant re-checks at evaluation time Future just-in-time compilation (JIT) has become easier, as demonstrated by released patches intended to be merged in a later release, for primarily two reasons: Firstly, due to a stricter split between expression initialization and evaluation, less code has to be handled by the JIT. Secondly, due to the non-recursive nature of the generated "instructions", less performance-critical code-paths can easily be shared between interpreted and compiled evaluation. The new framework allows for significant future optimizations. E.g.: - basic infrastructure for to later reduce the per executor-startup overhead of expression evaluation, by caching state in prepared statements. That'd be helpful in OLTPish scenarios where initialization overhead is measurable. - optimizing the generated "code". A number of proposals for potential work has already been made. - optimizing the interpreter. Similarly a number of proposals have been made here too. The move of logic into the expression initialization step leads to some backward-incompatible changes: - Function permission checks are now done during expression initialization, whereas previously they were done during execution. In edge cases this can lead to errors being raised that previously wouldn't have been, e.g. a NULL array being coerced to a different array type previously didn't perform checks. - The set of domain constraints to be checked, is now evaluated once during expression initialization, previously it was re-built every time a domain check was evaluated. For normal queries this doesn't change much, but e.g. for plpgsql functions, which caches ExprStates, the old set could stick around longer. The behavior around might still change. Author: Andres Freund, with significant changes by Tom Lane, changes by Heikki Linnakangas Reviewed-By: Tom Lane, Heikki Linnakangas Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
if (!ExecQual(predicate, econtext))
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
continue;
}
/*
* FormIndexDatum fills in its values and isnull parameters with the
* appropriate values for the column(s) of the index.
*/
FormIndexDatum(indexInfo,
slot,
estate,
values,
isnull);
satisfiesConstraint =
check_exclusion_or_unique_constraint(heapRelation, indexRelation,
indexInfo, &invalidItemPtr,
values, isnull, estate, false,
CEOUC_WAIT, true,
conflictTid);
if (!satisfiesConstraint)
return false;
}
if (arbiterIndexes != NIL && !checkedIndex)
elog(ERROR, "unexpected failure to find arbiter index");
return true;
}
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
/*
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* Check for violation of an exclusion or unique constraint
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
*
* heap: the table containing the new tuple
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* index: the index supporting the constraint
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
* indexInfo: info about the index, including the exclusion properties
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* tupleid: heap TID of the new tuple we have just inserted (invalid if we
* haven't inserted a new tuple yet)
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
* values, isnull: the *index* column values computed for the new tuple
* estate: an EState we can do evaluation in
* newIndex: if true, we are trying to build a new index (this affects
* only the wording of error messages)
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* waitMode: whether to wait for concurrent inserters/deleters
* violationOK: if true, don't throw error for violation
* conflictTid: if not-NULL, the TID of the conflicting tuple is returned here
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
*
* Returns true if OK, false if actual or potential violation
*
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* 'waitMode' determines what happens if a conflict is detected with a tuple
* that was inserted or deleted by a transaction that's still running.
* CEOUC_WAIT means that we wait for the transaction to commit, before
* throwing an error or returning. CEOUC_NOWAIT means that we report the
* violation immediately; so the violation is only potential, and the caller
* must recheck sometime later. This behavior is convenient for deferred
* exclusion checks; we need not bother queuing a deferred event if there is
* definitely no conflict at insertion time.
*
* CEOUC_LIVELOCK_PREVENTING_WAIT is like CEOUC_NOWAIT, but we will sometimes
* wait anyway, to prevent livelocking if two transactions try inserting at
* the same time. This is used with speculative insertions, for INSERT ON
* CONFLICT statements. (See notes in file header)
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
*
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* If violationOK is true, we just report the potential or actual violation to
* the caller by returning 'false'. Otherwise we throw a descriptive error
* message here. When violationOK is false, a false result is impossible.
*
* Note: The indexam is normally responsible for checking unique constraints,
* so this normally only needs to be used for exclusion constraints. But this
* function is also called when doing a "pre-check" for conflicts on a unique
* constraint, when doing speculative insertion. Caller may use the returned
* conflict TID to take further steps.
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
*/
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
static bool
check_exclusion_or_unique_constraint(Relation heap, Relation index,
IndexInfo *indexInfo,
ItemPointer tupleid,
Datum *values, bool *isnull,
EState *estate, bool newIndex,
CEOUC_WAIT_MODE waitMode,
bool violationOK,
ItemPointer conflictTid)
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
{
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
Oid *constr_procs;
uint16 *constr_strats;
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
Oid *index_collations = index->rd_indcollation;
Indexes with INCLUDE columns and their support in B-tree This patch introduces INCLUDE clause to index definition. This clause specifies a list of columns which will be included as a non-key part in the index. The INCLUDE columns exist solely to allow more queries to benefit from index-only scans. Also, such columns don't need to have appropriate operator classes. Expressions are not supported as INCLUDE columns since they cannot be used in index-only scans. Index access methods supporting INCLUDE are indicated by amcaninclude flag in IndexAmRoutine. For now, only B-tree indexes support INCLUDE clause. In B-tree indexes INCLUDE columns are truncated from pivot index tuples (tuples located in non-leaf pages and high keys). Therefore, B-tree indexes now might have variable number of attributes. This patch also provides generic facility to support that: pivot tuples contain number of their attributes in t_tid.ip_posid. Free 13th bit of t_info is used for indicating that. This facility will simplify further support of index suffix truncation. The changes of above are backward-compatible, pg_upgrade doesn't need special handling of B-tree indexes for that. Bump catalog version Author: Anastasia Lubennikova with contribition by Alexander Korotkov and me Reviewed by: Peter Geoghegan, Tomas Vondra, Antonin Houska, Jeff Janes, David Rowley, Alexander Korotkov Discussion: https://www.postgresql.org/message-id/flat/56168952.4010101@postgrespro.ru
2018-04-07 22:00:39 +02:00
int indnkeyatts = IndexRelationGetNumberOfKeyAttributes(index);
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
IndexScanDesc index_scan;
ScanKeyData scankeys[INDEX_MAX_KEYS];
SnapshotData DirtySnapshot;
int i;
bool conflict;
bool found_self;
ExprContext *econtext;
TupleTableSlot *existing_slot;
TupleTableSlot *save_scantuple;
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
if (indexInfo->ii_ExclusionOps)
{
constr_procs = indexInfo->ii_ExclusionProcs;
constr_strats = indexInfo->ii_ExclusionStrats;
}
else
{
constr_procs = indexInfo->ii_UniqueProcs;
constr_strats = indexInfo->ii_UniqueStrats;
}
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
/*
Fix check_exclusion_or_unique_constraint for UNIQUE NULLS NOT DISTINCT. Adjusting this function was overlooked in commit 94aa7cc5f. The only visible symptom (so far) is that INSERT ... ON CONFLICT could go into an endless loop when inserting a null that has a conflict. Richard Guo and Tom Lane, per bug #17558 from Andrew Kesper Discussion: https://postgr.es/m/17558-3f6599ffcf52fd4a@postgresql.org
2022-08-04 20:16:26 +02:00
* If any of the input values are NULL, and the index uses the default
* nulls-are-distinct mode, the constraint check is assumed to pass (i.e.,
* we assume the operators are strict). Otherwise, we interpret the
* constraint as specifying IS NULL for each column whose input value is
* NULL.
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
*/
Fix check_exclusion_or_unique_constraint for UNIQUE NULLS NOT DISTINCT. Adjusting this function was overlooked in commit 94aa7cc5f. The only visible symptom (so far) is that INSERT ... ON CONFLICT could go into an endless loop when inserting a null that has a conflict. Richard Guo and Tom Lane, per bug #17558 from Andrew Kesper Discussion: https://postgr.es/m/17558-3f6599ffcf52fd4a@postgresql.org
2022-08-04 20:16:26 +02:00
if (!indexInfo->ii_NullsNotDistinct)
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
{
Fix check_exclusion_or_unique_constraint for UNIQUE NULLS NOT DISTINCT. Adjusting this function was overlooked in commit 94aa7cc5f. The only visible symptom (so far) is that INSERT ... ON CONFLICT could go into an endless loop when inserting a null that has a conflict. Richard Guo and Tom Lane, per bug #17558 from Andrew Kesper Discussion: https://postgr.es/m/17558-3f6599ffcf52fd4a@postgresql.org
2022-08-04 20:16:26 +02:00
for (i = 0; i < indnkeyatts; i++)
{
if (isnull[i])
return true;
}
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
}
/*
* Search the tuples that are in the index for any violations, including
* tuples that aren't visible yet.
*/
InitDirtySnapshot(DirtySnapshot);
Indexes with INCLUDE columns and their support in B-tree This patch introduces INCLUDE clause to index definition. This clause specifies a list of columns which will be included as a non-key part in the index. The INCLUDE columns exist solely to allow more queries to benefit from index-only scans. Also, such columns don't need to have appropriate operator classes. Expressions are not supported as INCLUDE columns since they cannot be used in index-only scans. Index access methods supporting INCLUDE are indicated by amcaninclude flag in IndexAmRoutine. For now, only B-tree indexes support INCLUDE clause. In B-tree indexes INCLUDE columns are truncated from pivot index tuples (tuples located in non-leaf pages and high keys). Therefore, B-tree indexes now might have variable number of attributes. This patch also provides generic facility to support that: pivot tuples contain number of their attributes in t_tid.ip_posid. Free 13th bit of t_info is used for indicating that. This facility will simplify further support of index suffix truncation. The changes of above are backward-compatible, pg_upgrade doesn't need special handling of B-tree indexes for that. Bump catalog version Author: Anastasia Lubennikova with contribition by Alexander Korotkov and me Reviewed by: Peter Geoghegan, Tomas Vondra, Antonin Houska, Jeff Janes, David Rowley, Alexander Korotkov Discussion: https://www.postgresql.org/message-id/flat/56168952.4010101@postgrespro.ru
2018-04-07 22:00:39 +02:00
for (i = 0; i < indnkeyatts; i++)
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
{
ScanKeyEntryInitialize(&scankeys[i],
Fix check_exclusion_or_unique_constraint for UNIQUE NULLS NOT DISTINCT. Adjusting this function was overlooked in commit 94aa7cc5f. The only visible symptom (so far) is that INSERT ... ON CONFLICT could go into an endless loop when inserting a null that has a conflict. Richard Guo and Tom Lane, per bug #17558 from Andrew Kesper Discussion: https://postgr.es/m/17558-3f6599ffcf52fd4a@postgresql.org
2022-08-04 20:16:26 +02:00
isnull[i] ? SK_ISNULL | SK_SEARCHNULL : 0,
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
i + 1,
constr_strats[i],
InvalidOid,
index_collations[i],
constr_procs[i],
values[i]);
}
/*
* Need a TupleTableSlot to put existing tuples in.
*
* To use FormIndexDatum, we have to make the econtext's scantuple point
* to this slot. Be sure to save and restore caller's value for
* scantuple.
*/
tableam: Add and use scan APIs. Too allow table accesses to be not directly dependent on heap, several new abstractions are needed. Specifically: 1) Heap scans need to be generalized into table scans. Do this by introducing TableScanDesc, which will be the "base class" for individual AMs. This contains the AM independent fields from HeapScanDesc. The previous heap_{beginscan,rescan,endscan} et al. have been replaced with a table_ version. There's no direct replacement for heap_getnext(), as that returned a HeapTuple, which is undesirable for a other AMs. Instead there's table_scan_getnextslot(). But note that heap_getnext() lives on, it's still used widely to access catalog tables. This is achieved by new scan_begin, scan_end, scan_rescan, scan_getnextslot callbacks. 2) The portion of parallel scans that's shared between backends need to be able to do so without the user doing per-AM work. To achieve that new parallelscan_{estimate, initialize, reinitialize} callbacks are introduced, which operate on a new ParallelTableScanDesc, which again can be subclassed by AMs. As it is likely that several AMs are going to be block oriented, block oriented callbacks that can be shared between such AMs are provided and used by heap. table_block_parallelscan_{estimate, intiialize, reinitialize} as callbacks, and table_block_parallelscan_{nextpage, init} for use in AMs. These operate on a ParallelBlockTableScanDesc. 3) Index scans need to be able to access tables to return a tuple, and there needs to be state across individual accesses to the heap to store state like buffers. That's now handled by introducing a sort-of-scan IndexFetchTable, which again is intended to be subclassed by individual AMs (for heap IndexFetchHeap). The relevant callbacks for an AM are index_fetch_{end, begin, reset} to create the necessary state, and index_fetch_tuple to retrieve an indexed tuple. Note that index_fetch_tuple implementations need to be smarter than just blindly fetching the tuples for AMs that have optimizations similar to heap's HOT - the currently alive tuple in the update chain needs to be fetched if appropriate. Similar to table_scan_getnextslot(), it's undesirable to continue to return HeapTuples. Thus index_fetch_heap (might want to rename that later) now accepts a slot as an argument. Core code doesn't have a lot of call sites performing index scans without going through the systable_* API (in contrast to loads of heap_getnext calls and working directly with HeapTuples). Index scans now store the result of a search in IndexScanDesc->xs_heaptid, rather than xs_ctup->t_self. As the target is not generally a HeapTuple anymore that seems cleaner. To be able to sensible adapt code to use the above, two further callbacks have been introduced: a) slot_callbacks returns a TupleTableSlotOps* suitable for creating slots capable of holding a tuple of the AMs type. table_slot_callbacks() and table_slot_create() are based upon that, but have additional logic to deal with views, foreign tables, etc. While this change could have been done separately, nearly all the call sites that needed to be adapted for the rest of this commit also would have been needed to be adapted for table_slot_callbacks(), making separation not worthwhile. b) tuple_satisfies_snapshot checks whether the tuple in a slot is currently visible according to a snapshot. That's required as a few places now don't have a buffer + HeapTuple around, but a slot (which in heap's case internally has that information). Additionally a few infrastructure changes were needed: I) SysScanDesc, as used by systable_{beginscan, getnext} et al. now internally uses a slot to keep track of tuples. While systable_getnext() still returns HeapTuples, and will so for the foreseeable future, the index API (see 1) above) now only deals with slots. The remainder, and largest part, of this commit is then adjusting all scans in postgres to use the new APIs. Author: Andres Freund, Haribabu Kommi, Alvaro Herrera Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de https://postgr.es/m/20160812231527.GA690404@alvherre.pgsql
2019-03-11 20:46:41 +01:00
existing_slot = table_slot_create(heap, NULL);
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
econtext = GetPerTupleExprContext(estate);
save_scantuple = econtext->ecxt_scantuple;
econtext->ecxt_scantuple = existing_slot;
/*
* May have to restart scan from this point if a potential conflict is
* found.
*/
retry:
conflict = false;
found_self = false;
Indexes with INCLUDE columns and their support in B-tree This patch introduces INCLUDE clause to index definition. This clause specifies a list of columns which will be included as a non-key part in the index. The INCLUDE columns exist solely to allow more queries to benefit from index-only scans. Also, such columns don't need to have appropriate operator classes. Expressions are not supported as INCLUDE columns since they cannot be used in index-only scans. Index access methods supporting INCLUDE are indicated by amcaninclude flag in IndexAmRoutine. For now, only B-tree indexes support INCLUDE clause. In B-tree indexes INCLUDE columns are truncated from pivot index tuples (tuples located in non-leaf pages and high keys). Therefore, B-tree indexes now might have variable number of attributes. This patch also provides generic facility to support that: pivot tuples contain number of their attributes in t_tid.ip_posid. Free 13th bit of t_info is used for indicating that. This facility will simplify further support of index suffix truncation. The changes of above are backward-compatible, pg_upgrade doesn't need special handling of B-tree indexes for that. Bump catalog version Author: Anastasia Lubennikova with contribition by Alexander Korotkov and me Reviewed by: Peter Geoghegan, Tomas Vondra, Antonin Houska, Jeff Janes, David Rowley, Alexander Korotkov Discussion: https://www.postgresql.org/message-id/flat/56168952.4010101@postgrespro.ru
2018-04-07 22:00:39 +02:00
index_scan = index_beginscan(heap, index, &DirtySnapshot, indnkeyatts, 0);
index_rescan(index_scan, scankeys, indnkeyatts, NULL, 0);
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
tableam: Add and use scan APIs. Too allow table accesses to be not directly dependent on heap, several new abstractions are needed. Specifically: 1) Heap scans need to be generalized into table scans. Do this by introducing TableScanDesc, which will be the "base class" for individual AMs. This contains the AM independent fields from HeapScanDesc. The previous heap_{beginscan,rescan,endscan} et al. have been replaced with a table_ version. There's no direct replacement for heap_getnext(), as that returned a HeapTuple, which is undesirable for a other AMs. Instead there's table_scan_getnextslot(). But note that heap_getnext() lives on, it's still used widely to access catalog tables. This is achieved by new scan_begin, scan_end, scan_rescan, scan_getnextslot callbacks. 2) The portion of parallel scans that's shared between backends need to be able to do so without the user doing per-AM work. To achieve that new parallelscan_{estimate, initialize, reinitialize} callbacks are introduced, which operate on a new ParallelTableScanDesc, which again can be subclassed by AMs. As it is likely that several AMs are going to be block oriented, block oriented callbacks that can be shared between such AMs are provided and used by heap. table_block_parallelscan_{estimate, intiialize, reinitialize} as callbacks, and table_block_parallelscan_{nextpage, init} for use in AMs. These operate on a ParallelBlockTableScanDesc. 3) Index scans need to be able to access tables to return a tuple, and there needs to be state across individual accesses to the heap to store state like buffers. That's now handled by introducing a sort-of-scan IndexFetchTable, which again is intended to be subclassed by individual AMs (for heap IndexFetchHeap). The relevant callbacks for an AM are index_fetch_{end, begin, reset} to create the necessary state, and index_fetch_tuple to retrieve an indexed tuple. Note that index_fetch_tuple implementations need to be smarter than just blindly fetching the tuples for AMs that have optimizations similar to heap's HOT - the currently alive tuple in the update chain needs to be fetched if appropriate. Similar to table_scan_getnextslot(), it's undesirable to continue to return HeapTuples. Thus index_fetch_heap (might want to rename that later) now accepts a slot as an argument. Core code doesn't have a lot of call sites performing index scans without going through the systable_* API (in contrast to loads of heap_getnext calls and working directly with HeapTuples). Index scans now store the result of a search in IndexScanDesc->xs_heaptid, rather than xs_ctup->t_self. As the target is not generally a HeapTuple anymore that seems cleaner. To be able to sensible adapt code to use the above, two further callbacks have been introduced: a) slot_callbacks returns a TupleTableSlotOps* suitable for creating slots capable of holding a tuple of the AMs type. table_slot_callbacks() and table_slot_create() are based upon that, but have additional logic to deal with views, foreign tables, etc. While this change could have been done separately, nearly all the call sites that needed to be adapted for the rest of this commit also would have been needed to be adapted for table_slot_callbacks(), making separation not worthwhile. b) tuple_satisfies_snapshot checks whether the tuple in a slot is currently visible according to a snapshot. That's required as a few places now don't have a buffer + HeapTuple around, but a slot (which in heap's case internally has that information). Additionally a few infrastructure changes were needed: I) SysScanDesc, as used by systable_{beginscan, getnext} et al. now internally uses a slot to keep track of tuples. While systable_getnext() still returns HeapTuples, and will so for the foreseeable future, the index API (see 1) above) now only deals with slots. The remainder, and largest part, of this commit is then adjusting all scans in postgres to use the new APIs. Author: Andres Freund, Haribabu Kommi, Alvaro Herrera Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de https://postgr.es/m/20160812231527.GA690404@alvherre.pgsql
2019-03-11 20:46:41 +01:00
while (index_getnext_slot(index_scan, ForwardScanDirection, existing_slot))
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
{
TransactionId xwait;
Avoid incorrectly indicating exclusion constraint wait INSERT ... ON CONFLICT's precheck may have to wait on the outcome of another insertion, which may or may not itself be a speculative insertion. This wait is not necessarily associated with an exclusion constraint, but was always reported that way in log messages if the wait happened to involve a tuple that had no speculative token. Initially discovered through use of ON CONFLICT DO NOTHING, where spurious references to exclusion constraints in log messages were more likely. Patch by Peter Geoghegan. Reviewed by Julien Rouhaud. Back-patch to 9.5 where INSERT ... ON CONFLICT was added.
2016-03-15 23:04:39 +01:00
XLTW_Oper reason_wait;
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
Datum existing_values[INDEX_MAX_KEYS];
bool existing_isnull[INDEX_MAX_KEYS];
char *error_new;
char *error_existing;
/*
* Ignore the entry for the tuple we're trying to check.
*/
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
if (ItemPointerIsValid(tupleid) &&
tableam: Add and use scan APIs. Too allow table accesses to be not directly dependent on heap, several new abstractions are needed. Specifically: 1) Heap scans need to be generalized into table scans. Do this by introducing TableScanDesc, which will be the "base class" for individual AMs. This contains the AM independent fields from HeapScanDesc. The previous heap_{beginscan,rescan,endscan} et al. have been replaced with a table_ version. There's no direct replacement for heap_getnext(), as that returned a HeapTuple, which is undesirable for a other AMs. Instead there's table_scan_getnextslot(). But note that heap_getnext() lives on, it's still used widely to access catalog tables. This is achieved by new scan_begin, scan_end, scan_rescan, scan_getnextslot callbacks. 2) The portion of parallel scans that's shared between backends need to be able to do so without the user doing per-AM work. To achieve that new parallelscan_{estimate, initialize, reinitialize} callbacks are introduced, which operate on a new ParallelTableScanDesc, which again can be subclassed by AMs. As it is likely that several AMs are going to be block oriented, block oriented callbacks that can be shared between such AMs are provided and used by heap. table_block_parallelscan_{estimate, intiialize, reinitialize} as callbacks, and table_block_parallelscan_{nextpage, init} for use in AMs. These operate on a ParallelBlockTableScanDesc. 3) Index scans need to be able to access tables to return a tuple, and there needs to be state across individual accesses to the heap to store state like buffers. That's now handled by introducing a sort-of-scan IndexFetchTable, which again is intended to be subclassed by individual AMs (for heap IndexFetchHeap). The relevant callbacks for an AM are index_fetch_{end, begin, reset} to create the necessary state, and index_fetch_tuple to retrieve an indexed tuple. Note that index_fetch_tuple implementations need to be smarter than just blindly fetching the tuples for AMs that have optimizations similar to heap's HOT - the currently alive tuple in the update chain needs to be fetched if appropriate. Similar to table_scan_getnextslot(), it's undesirable to continue to return HeapTuples. Thus index_fetch_heap (might want to rename that later) now accepts a slot as an argument. Core code doesn't have a lot of call sites performing index scans without going through the systable_* API (in contrast to loads of heap_getnext calls and working directly with HeapTuples). Index scans now store the result of a search in IndexScanDesc->xs_heaptid, rather than xs_ctup->t_self. As the target is not generally a HeapTuple anymore that seems cleaner. To be able to sensible adapt code to use the above, two further callbacks have been introduced: a) slot_callbacks returns a TupleTableSlotOps* suitable for creating slots capable of holding a tuple of the AMs type. table_slot_callbacks() and table_slot_create() are based upon that, but have additional logic to deal with views, foreign tables, etc. While this change could have been done separately, nearly all the call sites that needed to be adapted for the rest of this commit also would have been needed to be adapted for table_slot_callbacks(), making separation not worthwhile. b) tuple_satisfies_snapshot checks whether the tuple in a slot is currently visible according to a snapshot. That's required as a few places now don't have a buffer + HeapTuple around, but a slot (which in heap's case internally has that information). Additionally a few infrastructure changes were needed: I) SysScanDesc, as used by systable_{beginscan, getnext} et al. now internally uses a slot to keep track of tuples. While systable_getnext() still returns HeapTuples, and will so for the foreseeable future, the index API (see 1) above) now only deals with slots. The remainder, and largest part, of this commit is then adjusting all scans in postgres to use the new APIs. Author: Andres Freund, Haribabu Kommi, Alvaro Herrera Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de https://postgr.es/m/20160812231527.GA690404@alvherre.pgsql
2019-03-11 20:46:41 +01:00
ItemPointerEquals(tupleid, &existing_slot->tts_tid))
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
{
if (found_self) /* should not happen */
elog(ERROR, "found self tuple multiple times in index \"%s\"",
RelationGetRelationName(index));
found_self = true;
continue;
}
/*
* Extract the index column values and isnull flags from the existing
* tuple.
*/
FormIndexDatum(indexInfo, existing_slot, estate,
existing_values, existing_isnull);
/* If lossy indexscan, must recheck the condition */
if (index_scan->xs_recheck)
{
if (!index_recheck_constraint(index,
constr_procs,
existing_values,
existing_isnull,
values))
continue; /* tuple doesn't actually match, so no
* conflict */
}
/*
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* At this point we have either a conflict or a potential conflict.
*
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
* If an in-progress transaction is affecting the visibility of this
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* tuple, we need to wait for it to complete and then recheck (unless
* the caller requested not to). For simplicity we do rechecking by
* just restarting the whole scan --- this case probably doesn't
* happen often enough to be worth trying harder, and anyway we don't
* want to hold any index internal locks while waiting.
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
*/
xwait = TransactionIdIsValid(DirtySnapshot.xmin) ?
DirtySnapshot.xmin : DirtySnapshot.xmax;
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
if (TransactionIdIsValid(xwait) &&
(waitMode == CEOUC_WAIT ||
(waitMode == CEOUC_LIVELOCK_PREVENTING_WAIT &&
DirtySnapshot.speculativeToken &&
TransactionIdPrecedes(GetCurrentTransactionId(), xwait))))
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
{
Avoid incorrectly indicating exclusion constraint wait INSERT ... ON CONFLICT's precheck may have to wait on the outcome of another insertion, which may or may not itself be a speculative insertion. This wait is not necessarily associated with an exclusion constraint, but was always reported that way in log messages if the wait happened to involve a tuple that had no speculative token. Initially discovered through use of ON CONFLICT DO NOTHING, where spurious references to exclusion constraints in log messages were more likely. Patch by Peter Geoghegan. Reviewed by Julien Rouhaud. Back-patch to 9.5 where INSERT ... ON CONFLICT was added.
2016-03-15 23:04:39 +01:00
reason_wait = indexInfo->ii_ExclusionOps ?
XLTW_RecheckExclusionConstr : XLTW_InsertIndex;
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
index_endscan(index_scan);
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
if (DirtySnapshot.speculativeToken)
SpeculativeInsertionWait(DirtySnapshot.xmin,
DirtySnapshot.speculativeToken);
else
tableam: Add and use scan APIs. Too allow table accesses to be not directly dependent on heap, several new abstractions are needed. Specifically: 1) Heap scans need to be generalized into table scans. Do this by introducing TableScanDesc, which will be the "base class" for individual AMs. This contains the AM independent fields from HeapScanDesc. The previous heap_{beginscan,rescan,endscan} et al. have been replaced with a table_ version. There's no direct replacement for heap_getnext(), as that returned a HeapTuple, which is undesirable for a other AMs. Instead there's table_scan_getnextslot(). But note that heap_getnext() lives on, it's still used widely to access catalog tables. This is achieved by new scan_begin, scan_end, scan_rescan, scan_getnextslot callbacks. 2) The portion of parallel scans that's shared between backends need to be able to do so without the user doing per-AM work. To achieve that new parallelscan_{estimate, initialize, reinitialize} callbacks are introduced, which operate on a new ParallelTableScanDesc, which again can be subclassed by AMs. As it is likely that several AMs are going to be block oriented, block oriented callbacks that can be shared between such AMs are provided and used by heap. table_block_parallelscan_{estimate, intiialize, reinitialize} as callbacks, and table_block_parallelscan_{nextpage, init} for use in AMs. These operate on a ParallelBlockTableScanDesc. 3) Index scans need to be able to access tables to return a tuple, and there needs to be state across individual accesses to the heap to store state like buffers. That's now handled by introducing a sort-of-scan IndexFetchTable, which again is intended to be subclassed by individual AMs (for heap IndexFetchHeap). The relevant callbacks for an AM are index_fetch_{end, begin, reset} to create the necessary state, and index_fetch_tuple to retrieve an indexed tuple. Note that index_fetch_tuple implementations need to be smarter than just blindly fetching the tuples for AMs that have optimizations similar to heap's HOT - the currently alive tuple in the update chain needs to be fetched if appropriate. Similar to table_scan_getnextslot(), it's undesirable to continue to return HeapTuples. Thus index_fetch_heap (might want to rename that later) now accepts a slot as an argument. Core code doesn't have a lot of call sites performing index scans without going through the systable_* API (in contrast to loads of heap_getnext calls and working directly with HeapTuples). Index scans now store the result of a search in IndexScanDesc->xs_heaptid, rather than xs_ctup->t_self. As the target is not generally a HeapTuple anymore that seems cleaner. To be able to sensible adapt code to use the above, two further callbacks have been introduced: a) slot_callbacks returns a TupleTableSlotOps* suitable for creating slots capable of holding a tuple of the AMs type. table_slot_callbacks() and table_slot_create() are based upon that, but have additional logic to deal with views, foreign tables, etc. While this change could have been done separately, nearly all the call sites that needed to be adapted for the rest of this commit also would have been needed to be adapted for table_slot_callbacks(), making separation not worthwhile. b) tuple_satisfies_snapshot checks whether the tuple in a slot is currently visible according to a snapshot. That's required as a few places now don't have a buffer + HeapTuple around, but a slot (which in heap's case internally has that information). Additionally a few infrastructure changes were needed: I) SysScanDesc, as used by systable_{beginscan, getnext} et al. now internally uses a slot to keep track of tuples. While systable_getnext() still returns HeapTuples, and will so for the foreseeable future, the index API (see 1) above) now only deals with slots. The remainder, and largest part, of this commit is then adjusting all scans in postgres to use the new APIs. Author: Andres Freund, Haribabu Kommi, Alvaro Herrera Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de https://postgr.es/m/20160812231527.GA690404@alvherre.pgsql
2019-03-11 20:46:41 +01:00
XactLockTableWait(xwait, heap,
&existing_slot->tts_tid, reason_wait);
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
goto retry;
}
/*
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* We have a definite conflict (or a potential one, but the caller
* didn't want to wait). Return it to caller, or report it.
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
*/
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
if (violationOK)
{
conflict = true;
if (conflictTid)
tableam: Add and use scan APIs. Too allow table accesses to be not directly dependent on heap, several new abstractions are needed. Specifically: 1) Heap scans need to be generalized into table scans. Do this by introducing TableScanDesc, which will be the "base class" for individual AMs. This contains the AM independent fields from HeapScanDesc. The previous heap_{beginscan,rescan,endscan} et al. have been replaced with a table_ version. There's no direct replacement for heap_getnext(), as that returned a HeapTuple, which is undesirable for a other AMs. Instead there's table_scan_getnextslot(). But note that heap_getnext() lives on, it's still used widely to access catalog tables. This is achieved by new scan_begin, scan_end, scan_rescan, scan_getnextslot callbacks. 2) The portion of parallel scans that's shared between backends need to be able to do so without the user doing per-AM work. To achieve that new parallelscan_{estimate, initialize, reinitialize} callbacks are introduced, which operate on a new ParallelTableScanDesc, which again can be subclassed by AMs. As it is likely that several AMs are going to be block oriented, block oriented callbacks that can be shared between such AMs are provided and used by heap. table_block_parallelscan_{estimate, intiialize, reinitialize} as callbacks, and table_block_parallelscan_{nextpage, init} for use in AMs. These operate on a ParallelBlockTableScanDesc. 3) Index scans need to be able to access tables to return a tuple, and there needs to be state across individual accesses to the heap to store state like buffers. That's now handled by introducing a sort-of-scan IndexFetchTable, which again is intended to be subclassed by individual AMs (for heap IndexFetchHeap). The relevant callbacks for an AM are index_fetch_{end, begin, reset} to create the necessary state, and index_fetch_tuple to retrieve an indexed tuple. Note that index_fetch_tuple implementations need to be smarter than just blindly fetching the tuples for AMs that have optimizations similar to heap's HOT - the currently alive tuple in the update chain needs to be fetched if appropriate. Similar to table_scan_getnextslot(), it's undesirable to continue to return HeapTuples. Thus index_fetch_heap (might want to rename that later) now accepts a slot as an argument. Core code doesn't have a lot of call sites performing index scans without going through the systable_* API (in contrast to loads of heap_getnext calls and working directly with HeapTuples). Index scans now store the result of a search in IndexScanDesc->xs_heaptid, rather than xs_ctup->t_self. As the target is not generally a HeapTuple anymore that seems cleaner. To be able to sensible adapt code to use the above, two further callbacks have been introduced: a) slot_callbacks returns a TupleTableSlotOps* suitable for creating slots capable of holding a tuple of the AMs type. table_slot_callbacks() and table_slot_create() are based upon that, but have additional logic to deal with views, foreign tables, etc. While this change could have been done separately, nearly all the call sites that needed to be adapted for the rest of this commit also would have been needed to be adapted for table_slot_callbacks(), making separation not worthwhile. b) tuple_satisfies_snapshot checks whether the tuple in a slot is currently visible according to a snapshot. That's required as a few places now don't have a buffer + HeapTuple around, but a slot (which in heap's case internally has that information). Additionally a few infrastructure changes were needed: I) SysScanDesc, as used by systable_{beginscan, getnext} et al. now internally uses a slot to keep track of tuples. While systable_getnext() still returns HeapTuples, and will so for the foreseeable future, the index API (see 1) above) now only deals with slots. The remainder, and largest part, of this commit is then adjusting all scans in postgres to use the new APIs. Author: Andres Freund, Haribabu Kommi, Alvaro Herrera Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de https://postgr.es/m/20160812231527.GA690404@alvherre.pgsql
2019-03-11 20:46:41 +01:00
*conflictTid = existing_slot->tts_tid;
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
break;
}
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
error_new = BuildIndexValueDescription(index, values, isnull);
error_existing = BuildIndexValueDescription(index, existing_values,
existing_isnull);
if (newIndex)
ereport(ERROR,
(errcode(ERRCODE_EXCLUSION_VIOLATION),
errmsg("could not create exclusion constraint \"%s\"",
RelationGetRelationName(index)),
error_new && error_existing ?
errdetail("Key %s conflicts with key %s.",
error_new, error_existing) :
errdetail("Key conflicts exist."),
errtableconstraint(heap,
RelationGetRelationName(index))));
else
ereport(ERROR,
(errcode(ERRCODE_EXCLUSION_VIOLATION),
errmsg("conflicting key value violates exclusion constraint \"%s\"",
RelationGetRelationName(index)),
error_new && error_existing ?
errdetail("Key %s conflicts with existing key %s.",
error_new, error_existing) :
errdetail("Key conflicts with existing key."),
errtableconstraint(heap,
RelationGetRelationName(index))));
}
index_endscan(index_scan);
/*
* Ordinarily, at this point the search should have found the originally
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
* inserted tuple (if any), unless we exited the loop early because of
* conflict. However, it is possible to define exclusion constraints for
* which that wouldn't be true --- for instance, if the operator is <>. So
* we no longer complain if found_self is still false.
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
*/
econtext->ecxt_scantuple = save_scantuple;
ExecDropSingleTupleTableSlot(existing_slot);
return !conflict;
}
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
/*
* Check for violation of an exclusion constraint
*
* This is a dumbed down version of check_exclusion_or_unique_constraint
* for external callers. They don't need all the special modes.
*/
void
check_exclusion_constraint(Relation heap, Relation index,
IndexInfo *indexInfo,
ItemPointer tupleid,
Datum *values, bool *isnull,
EState *estate, bool newIndex)
{
(void) check_exclusion_or_unique_constraint(heap, index, indexInfo, tupleid,
values, isnull,
estate, newIndex,
CEOUC_WAIT, false, NULL);
}
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
/*
* Check existing tuple's index values to see if it really matches the
* exclusion condition against the new_values. Returns true if conflict.
*/
static bool
index_recheck_constraint(Relation index, Oid *constr_procs,
Datum *existing_values, bool *existing_isnull,
Datum *new_values)
{
Indexes with INCLUDE columns and their support in B-tree This patch introduces INCLUDE clause to index definition. This clause specifies a list of columns which will be included as a non-key part in the index. The INCLUDE columns exist solely to allow more queries to benefit from index-only scans. Also, such columns don't need to have appropriate operator classes. Expressions are not supported as INCLUDE columns since they cannot be used in index-only scans. Index access methods supporting INCLUDE are indicated by amcaninclude flag in IndexAmRoutine. For now, only B-tree indexes support INCLUDE clause. In B-tree indexes INCLUDE columns are truncated from pivot index tuples (tuples located in non-leaf pages and high keys). Therefore, B-tree indexes now might have variable number of attributes. This patch also provides generic facility to support that: pivot tuples contain number of their attributes in t_tid.ip_posid. Free 13th bit of t_info is used for indicating that. This facility will simplify further support of index suffix truncation. The changes of above are backward-compatible, pg_upgrade doesn't need special handling of B-tree indexes for that. Bump catalog version Author: Anastasia Lubennikova with contribition by Alexander Korotkov and me Reviewed by: Peter Geoghegan, Tomas Vondra, Antonin Houska, Jeff Janes, David Rowley, Alexander Korotkov Discussion: https://www.postgresql.org/message-id/flat/56168952.4010101@postgrespro.ru
2018-04-07 22:00:39 +02:00
int indnkeyatts = IndexRelationGetNumberOfKeyAttributes(index);
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
int i;
Indexes with INCLUDE columns and their support in B-tree This patch introduces INCLUDE clause to index definition. This clause specifies a list of columns which will be included as a non-key part in the index. The INCLUDE columns exist solely to allow more queries to benefit from index-only scans. Also, such columns don't need to have appropriate operator classes. Expressions are not supported as INCLUDE columns since they cannot be used in index-only scans. Index access methods supporting INCLUDE are indicated by amcaninclude flag in IndexAmRoutine. For now, only B-tree indexes support INCLUDE clause. In B-tree indexes INCLUDE columns are truncated from pivot index tuples (tuples located in non-leaf pages and high keys). Therefore, B-tree indexes now might have variable number of attributes. This patch also provides generic facility to support that: pivot tuples contain number of their attributes in t_tid.ip_posid. Free 13th bit of t_info is used for indicating that. This facility will simplify further support of index suffix truncation. The changes of above are backward-compatible, pg_upgrade doesn't need special handling of B-tree indexes for that. Bump catalog version Author: Anastasia Lubennikova with contribition by Alexander Korotkov and me Reviewed by: Peter Geoghegan, Tomas Vondra, Antonin Houska, Jeff Janes, David Rowley, Alexander Korotkov Discussion: https://www.postgresql.org/message-id/flat/56168952.4010101@postgrespro.ru
2018-04-07 22:00:39 +02:00
for (i = 0; i < indnkeyatts; i++)
Move functions related to index maintenance to separate source file. There is enough code here to deserve a file of their own, not be buried in the middle of execUtils.c.
2015-04-24 08:33:23 +02:00
{
/* Assume the exclusion operators are strict */
if (existing_isnull[i])
return false;
if (!DatumGetBool(OidFunctionCall2Coll(constr_procs[i],
index->rd_indcollation[i],
existing_values[i],
new_values[i])))
return false;
}
return true;
}
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
/*
* Check if ExecInsertIndexTuples() should pass indexUnchanged hint.
*
* When the executor performs an UPDATE that requires a new round of index
* tuples, determine if we should pass 'indexUnchanged' = true hint for one
* single index.
*/
static bool
index_unchanged_by_update(ResultRelInfo *resultRelInfo, EState *estate,
IndexInfo *indexInfo, Relation indexRelation)
{
Fix memory leak in indexUnchanged hint mechanism. Commit 9dc718bd added a "logically unchanged by UPDATE" hinting mechanism, which is currently used within nbtree indexes only (see commit d168b666). This mechanism determined whether or not the incoming item is a logically unchanged duplicate (a duplicate needed only for MVCC versioning purposes) once per row updated per non-HOT update. This approach led to memory leaks which were noticeable with an UPDATE statement that updated sufficiently many rows, at least on tables that happen to have an expression index. On HEAD, fix the issue by adding a cache to the executor's per-index IndexInfo struct. Take a different approach on Postgres 14 to avoid an ABI break: simply pass down the hint to all indexes unconditionally with non-HOT UPDATEs. This is deemed acceptable because the hint is currently interpreted within btinsert() as "perform a bottom-up index deletion pass if and when the only alternative is splitting the leaf page -- prefer to delete any LP_DEAD-set items first". nbtree must always treat the hint as a noisy signal about what might work, as a strategy of last resort, with costs imposed on non-HOT updaters. (The same thing might not be true within another index AM that applies the hint, which is why the original behavior is preserved on HEAD.) Author: Peter Geoghegan <pg@bowt.ie> Reported-By: Klaudie Willis <Klaudie.Willis@protonmail.com> Diagnosed-By: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/261065.1639497535@sss.pgh.pa.us Backpatch: 14-, where the hinting mechanism was added.
2022-01-13 00:41:04 +01:00
Bitmapset *updatedCols;
Bitmapset *extraUpdatedCols;
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
Bitmapset *allUpdatedCols;
bool hasexpression = false;
List *idxExprs;
Fix memory leak in indexUnchanged hint mechanism. Commit 9dc718bd added a "logically unchanged by UPDATE" hinting mechanism, which is currently used within nbtree indexes only (see commit d168b666). This mechanism determined whether or not the incoming item is a logically unchanged duplicate (a duplicate needed only for MVCC versioning purposes) once per row updated per non-HOT update. This approach led to memory leaks which were noticeable with an UPDATE statement that updated sufficiently many rows, at least on tables that happen to have an expression index. On HEAD, fix the issue by adding a cache to the executor's per-index IndexInfo struct. Take a different approach on Postgres 14 to avoid an ABI break: simply pass down the hint to all indexes unconditionally with non-HOT UPDATEs. This is deemed acceptable because the hint is currently interpreted within btinsert() as "perform a bottom-up index deletion pass if and when the only alternative is splitting the leaf page -- prefer to delete any LP_DEAD-set items first". nbtree must always treat the hint as a noisy signal about what might work, as a strategy of last resort, with costs imposed on non-HOT updaters. (The same thing might not be true within another index AM that applies the hint, which is why the original behavior is preserved on HEAD.) Author: Peter Geoghegan <pg@bowt.ie> Reported-By: Klaudie Willis <Klaudie.Willis@protonmail.com> Diagnosed-By: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/261065.1639497535@sss.pgh.pa.us Backpatch: 14-, where the hinting mechanism was added.
2022-01-13 00:41:04 +01:00
/*
* Check cache first
*/
if (indexInfo->ii_CheckedUnchanged)
return indexInfo->ii_IndexUnchanged;
indexInfo->ii_CheckedUnchanged = true;
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
/*
* Check for indexed attribute overlap with updated columns.
*
* Only do this for key columns. A change to a non-key column within an
* INCLUDE index should not be counted here. Non-key column values are
* opaque payload state to the index AM, a little like an extra table TID.
Fix memory leak in indexUnchanged hint mechanism. Commit 9dc718bd added a "logically unchanged by UPDATE" hinting mechanism, which is currently used within nbtree indexes only (see commit d168b666). This mechanism determined whether or not the incoming item is a logically unchanged duplicate (a duplicate needed only for MVCC versioning purposes) once per row updated per non-HOT update. This approach led to memory leaks which were noticeable with an UPDATE statement that updated sufficiently many rows, at least on tables that happen to have an expression index. On HEAD, fix the issue by adding a cache to the executor's per-index IndexInfo struct. Take a different approach on Postgres 14 to avoid an ABI break: simply pass down the hint to all indexes unconditionally with non-HOT UPDATEs. This is deemed acceptable because the hint is currently interpreted within btinsert() as "perform a bottom-up index deletion pass if and when the only alternative is splitting the leaf page -- prefer to delete any LP_DEAD-set items first". nbtree must always treat the hint as a noisy signal about what might work, as a strategy of last resort, with costs imposed on non-HOT updaters. (The same thing might not be true within another index AM that applies the hint, which is why the original behavior is preserved on HEAD.) Author: Peter Geoghegan <pg@bowt.ie> Reported-By: Klaudie Willis <Klaudie.Willis@protonmail.com> Diagnosed-By: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/261065.1639497535@sss.pgh.pa.us Backpatch: 14-, where the hinting mechanism was added.
2022-01-13 00:41:04 +01:00
*
* Note that row-level BEFORE triggers won't affect our behavior, since
* they don't affect the updatedCols bitmaps generally. It doesn't seem
* worth the trouble of checking which attributes were changed directly.
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
*/
Fix memory leak in indexUnchanged hint mechanism. Commit 9dc718bd added a "logically unchanged by UPDATE" hinting mechanism, which is currently used within nbtree indexes only (see commit d168b666). This mechanism determined whether or not the incoming item is a logically unchanged duplicate (a duplicate needed only for MVCC versioning purposes) once per row updated per non-HOT update. This approach led to memory leaks which were noticeable with an UPDATE statement that updated sufficiently many rows, at least on tables that happen to have an expression index. On HEAD, fix the issue by adding a cache to the executor's per-index IndexInfo struct. Take a different approach on Postgres 14 to avoid an ABI break: simply pass down the hint to all indexes unconditionally with non-HOT UPDATEs. This is deemed acceptable because the hint is currently interpreted within btinsert() as "perform a bottom-up index deletion pass if and when the only alternative is splitting the leaf page -- prefer to delete any LP_DEAD-set items first". nbtree must always treat the hint as a noisy signal about what might work, as a strategy of last resort, with costs imposed on non-HOT updaters. (The same thing might not be true within another index AM that applies the hint, which is why the original behavior is preserved on HEAD.) Author: Peter Geoghegan <pg@bowt.ie> Reported-By: Klaudie Willis <Klaudie.Willis@protonmail.com> Diagnosed-By: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/261065.1639497535@sss.pgh.pa.us Backpatch: 14-, where the hinting mechanism was added.
2022-01-13 00:41:04 +01:00
updatedCols = ExecGetUpdatedCols(resultRelInfo, estate);
extraUpdatedCols = ExecGetExtraUpdatedCols(resultRelInfo, estate);
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
for (int attr = 0; attr < indexInfo->ii_NumIndexKeyAttrs; attr++)
{
int keycol = indexInfo->ii_IndexAttrNumbers[attr];
if (keycol <= 0)
{
/*
* Skip expressions for now, but remember to deal with them later
* on
*/
hasexpression = true;
continue;
}
if (bms_is_member(keycol - FirstLowInvalidHeapAttributeNumber,
updatedCols) ||
bms_is_member(keycol - FirstLowInvalidHeapAttributeNumber,
extraUpdatedCols))
{
/* Changed key column -- don't hint for this index */
Fix memory leak in indexUnchanged hint mechanism. Commit 9dc718bd added a "logically unchanged by UPDATE" hinting mechanism, which is currently used within nbtree indexes only (see commit d168b666). This mechanism determined whether or not the incoming item is a logically unchanged duplicate (a duplicate needed only for MVCC versioning purposes) once per row updated per non-HOT update. This approach led to memory leaks which were noticeable with an UPDATE statement that updated sufficiently many rows, at least on tables that happen to have an expression index. On HEAD, fix the issue by adding a cache to the executor's per-index IndexInfo struct. Take a different approach on Postgres 14 to avoid an ABI break: simply pass down the hint to all indexes unconditionally with non-HOT UPDATEs. This is deemed acceptable because the hint is currently interpreted within btinsert() as "perform a bottom-up index deletion pass if and when the only alternative is splitting the leaf page -- prefer to delete any LP_DEAD-set items first". nbtree must always treat the hint as a noisy signal about what might work, as a strategy of last resort, with costs imposed on non-HOT updaters. (The same thing might not be true within another index AM that applies the hint, which is why the original behavior is preserved on HEAD.) Author: Peter Geoghegan <pg@bowt.ie> Reported-By: Klaudie Willis <Klaudie.Willis@protonmail.com> Diagnosed-By: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/261065.1639497535@sss.pgh.pa.us Backpatch: 14-, where the hinting mechanism was added.
2022-01-13 00:41:04 +01:00
indexInfo->ii_IndexUnchanged = false;
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
return false;
}
}
/*
* When we get this far and index has no expressions, return true so that
* index_insert() call will go on to pass 'indexUnchanged' = true hint.
*
* The _absence_ of an indexed key attribute that overlaps with updated
* attributes (in addition to the total absence of indexed expressions)
* shows that the index as a whole is logically unchanged by UPDATE.
*/
if (!hasexpression)
Fix memory leak in indexUnchanged hint mechanism. Commit 9dc718bd added a "logically unchanged by UPDATE" hinting mechanism, which is currently used within nbtree indexes only (see commit d168b666). This mechanism determined whether or not the incoming item is a logically unchanged duplicate (a duplicate needed only for MVCC versioning purposes) once per row updated per non-HOT update. This approach led to memory leaks which were noticeable with an UPDATE statement that updated sufficiently many rows, at least on tables that happen to have an expression index. On HEAD, fix the issue by adding a cache to the executor's per-index IndexInfo struct. Take a different approach on Postgres 14 to avoid an ABI break: simply pass down the hint to all indexes unconditionally with non-HOT UPDATEs. This is deemed acceptable because the hint is currently interpreted within btinsert() as "perform a bottom-up index deletion pass if and when the only alternative is splitting the leaf page -- prefer to delete any LP_DEAD-set items first". nbtree must always treat the hint as a noisy signal about what might work, as a strategy of last resort, with costs imposed on non-HOT updaters. (The same thing might not be true within another index AM that applies the hint, which is why the original behavior is preserved on HEAD.) Author: Peter Geoghegan <pg@bowt.ie> Reported-By: Klaudie Willis <Klaudie.Willis@protonmail.com> Diagnosed-By: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/261065.1639497535@sss.pgh.pa.us Backpatch: 14-, where the hinting mechanism was added.
2022-01-13 00:41:04 +01:00
{
indexInfo->ii_IndexUnchanged = true;
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
return true;
Fix memory leak in indexUnchanged hint mechanism. Commit 9dc718bd added a "logically unchanged by UPDATE" hinting mechanism, which is currently used within nbtree indexes only (see commit d168b666). This mechanism determined whether or not the incoming item is a logically unchanged duplicate (a duplicate needed only for MVCC versioning purposes) once per row updated per non-HOT update. This approach led to memory leaks which were noticeable with an UPDATE statement that updated sufficiently many rows, at least on tables that happen to have an expression index. On HEAD, fix the issue by adding a cache to the executor's per-index IndexInfo struct. Take a different approach on Postgres 14 to avoid an ABI break: simply pass down the hint to all indexes unconditionally with non-HOT UPDATEs. This is deemed acceptable because the hint is currently interpreted within btinsert() as "perform a bottom-up index deletion pass if and when the only alternative is splitting the leaf page -- prefer to delete any LP_DEAD-set items first". nbtree must always treat the hint as a noisy signal about what might work, as a strategy of last resort, with costs imposed on non-HOT updaters. (The same thing might not be true within another index AM that applies the hint, which is why the original behavior is preserved on HEAD.) Author: Peter Geoghegan <pg@bowt.ie> Reported-By: Klaudie Willis <Klaudie.Willis@protonmail.com> Diagnosed-By: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/261065.1639497535@sss.pgh.pa.us Backpatch: 14-, where the hinting mechanism was added.
2022-01-13 00:41:04 +01:00
}
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
/*
* Need to pass only one bms to expression_tree_walker helper function.
* Avoid allocating memory in common case where there are no extra cols.
*/
if (!extraUpdatedCols)
allUpdatedCols = updatedCols;
else
allUpdatedCols = bms_union(updatedCols, extraUpdatedCols);
/*
* We have to work slightly harder in the event of indexed expressions,
* but the principle is the same as before: try to find columns (Vars,
* actually) that overlap with known-updated columns.
*
* If we find any matching Vars, don't pass hint for index. Otherwise
* pass hint.
*/
idxExprs = RelationGetIndexExpressions(indexRelation);
hasexpression = index_expression_changed_walker((Node *) idxExprs,
allUpdatedCols);
list_free(idxExprs);
if (extraUpdatedCols)
bms_free(allUpdatedCols);
if (hasexpression)
Fix memory leak in indexUnchanged hint mechanism. Commit 9dc718bd added a "logically unchanged by UPDATE" hinting mechanism, which is currently used within nbtree indexes only (see commit d168b666). This mechanism determined whether or not the incoming item is a logically unchanged duplicate (a duplicate needed only for MVCC versioning purposes) once per row updated per non-HOT update. This approach led to memory leaks which were noticeable with an UPDATE statement that updated sufficiently many rows, at least on tables that happen to have an expression index. On HEAD, fix the issue by adding a cache to the executor's per-index IndexInfo struct. Take a different approach on Postgres 14 to avoid an ABI break: simply pass down the hint to all indexes unconditionally with non-HOT UPDATEs. This is deemed acceptable because the hint is currently interpreted within btinsert() as "perform a bottom-up index deletion pass if and when the only alternative is splitting the leaf page -- prefer to delete any LP_DEAD-set items first". nbtree must always treat the hint as a noisy signal about what might work, as a strategy of last resort, with costs imposed on non-HOT updaters. (The same thing might not be true within another index AM that applies the hint, which is why the original behavior is preserved on HEAD.) Author: Peter Geoghegan <pg@bowt.ie> Reported-By: Klaudie Willis <Klaudie.Willis@protonmail.com> Diagnosed-By: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/261065.1639497535@sss.pgh.pa.us Backpatch: 14-, where the hinting mechanism was added.
2022-01-13 00:41:04 +01:00
{
indexInfo->ii_IndexUnchanged = false;
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
return false;
Fix memory leak in indexUnchanged hint mechanism. Commit 9dc718bd added a "logically unchanged by UPDATE" hinting mechanism, which is currently used within nbtree indexes only (see commit d168b666). This mechanism determined whether or not the incoming item is a logically unchanged duplicate (a duplicate needed only for MVCC versioning purposes) once per row updated per non-HOT update. This approach led to memory leaks which were noticeable with an UPDATE statement that updated sufficiently many rows, at least on tables that happen to have an expression index. On HEAD, fix the issue by adding a cache to the executor's per-index IndexInfo struct. Take a different approach on Postgres 14 to avoid an ABI break: simply pass down the hint to all indexes unconditionally with non-HOT UPDATEs. This is deemed acceptable because the hint is currently interpreted within btinsert() as "perform a bottom-up index deletion pass if and when the only alternative is splitting the leaf page -- prefer to delete any LP_DEAD-set items first". nbtree must always treat the hint as a noisy signal about what might work, as a strategy of last resort, with costs imposed on non-HOT updaters. (The same thing might not be true within another index AM that applies the hint, which is why the original behavior is preserved on HEAD.) Author: Peter Geoghegan <pg@bowt.ie> Reported-By: Klaudie Willis <Klaudie.Willis@protonmail.com> Diagnosed-By: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/261065.1639497535@sss.pgh.pa.us Backpatch: 14-, where the hinting mechanism was added.
2022-01-13 00:41:04 +01:00
}
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
Fix memory leak in indexUnchanged hint mechanism. Commit 9dc718bd added a "logically unchanged by UPDATE" hinting mechanism, which is currently used within nbtree indexes only (see commit d168b666). This mechanism determined whether or not the incoming item is a logically unchanged duplicate (a duplicate needed only for MVCC versioning purposes) once per row updated per non-HOT update. This approach led to memory leaks which were noticeable with an UPDATE statement that updated sufficiently many rows, at least on tables that happen to have an expression index. On HEAD, fix the issue by adding a cache to the executor's per-index IndexInfo struct. Take a different approach on Postgres 14 to avoid an ABI break: simply pass down the hint to all indexes unconditionally with non-HOT UPDATEs. This is deemed acceptable because the hint is currently interpreted within btinsert() as "perform a bottom-up index deletion pass if and when the only alternative is splitting the leaf page -- prefer to delete any LP_DEAD-set items first". nbtree must always treat the hint as a noisy signal about what might work, as a strategy of last resort, with costs imposed on non-HOT updaters. (The same thing might not be true within another index AM that applies the hint, which is why the original behavior is preserved on HEAD.) Author: Peter Geoghegan <pg@bowt.ie> Reported-By: Klaudie Willis <Klaudie.Willis@protonmail.com> Diagnosed-By: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/261065.1639497535@sss.pgh.pa.us Backpatch: 14-, where the hinting mechanism was added.
2022-01-13 00:41:04 +01:00
/*
* Deliberately don't consider index predicates. We should even give the
* hint when result rel's "updated tuple" has no corresponding index
* tuple, which is possible with a partial index (provided the usual
* conditions are met).
*/
indexInfo->ii_IndexUnchanged = true;
Pass down "logically unchanged index" hint. Add an executor aminsert() hint mechanism that informs index AMs that the incoming index tuple (the tuple that accompanies the hint) is not being inserted by execution of an SQL statement that logically modifies any of the index's key columns. The hint is received by indexes when an UPDATE takes place that does not apply an optimization like heapam's HOT (though only for indexes where all key columns are logically unchanged). Any index tuple that receives the hint on insert is expected to be a duplicate of at least one existing older version that is needed for the same logical row. Related versions will typically be stored on the same index page, at least within index AMs that apply the hint. Recognizing the difference between MVCC version churn duplicates and true logical row duplicates at the index AM level can help with cleanup of garbage index tuples. Cleanup can intelligently target tuples that are likely to be garbage, without wasting too many cycles on less promising tuples/pages (index pages with little or no version churn). This is infrastructure for an upcoming commit that will teach nbtree to perform bottom-up index deletion. No index AM actually applies the hint just yet. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Victor Yegorov <vyegorov@gmail.com> Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
2021-01-13 17:11:00 +01:00
return true;
}
/*
* Indexed expression helper for index_unchanged_by_update().
*
* Returns true when Var that appears within allUpdatedCols located.
*/
static bool
index_expression_changed_walker(Node *node, Bitmapset *allUpdatedCols)
{
if (node == NULL)
return false;
if (IsA(node, Var))
{
Var *var = (Var *) node;
if (bms_is_member(var->varattno - FirstLowInvalidHeapAttributeNumber,
allUpdatedCols))
{
/* Var was updated -- indicates that we should not hint */
return true;
}
/* Still haven't found a reason to not pass the hint */
return false;
}
return expression_tree_walker(node, index_expression_changed_walker,
(void *) allUpdatedCols);
}