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postgresql/src/include/access/amapi.h

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Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
/*-------------------------------------------------------------------------
*
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
* amapi.h
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
* API for Postgres index access methods.
*
Update copyright for 2023 Backpatch-through: 11
2023-01-02 21:00:37 +01:00
* Copyright (c) 2015-2023, PostgreSQL Global Development Group
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
*
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
* src/include/access/amapi.h
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
*
*-------------------------------------------------------------------------
*/
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
#ifndef AMAPI_H
#define AMAPI_H
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
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"
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
/*
* We don't wish to include planner header files here, since most of an index
* AM's implementation isn't concerned with those data structures. To allow
* declaring amcostestimate_function here, use forward struct references.
*/
struct PlannerInfo;
struct IndexPath;
/* Likewise, this file shouldn't depend on execnodes.h. */
struct IndexInfo;
Add SQL-accessible functions for inspecting index AM properties. Per discussion, we should provide such functions to replace the lost ability to discover AM properties by inspecting pg_am (cf commit 65c5fcd35). The added functionality is also meant to displace any code that was looking directly at pg_index.indoption, since we'd rather not believe that the bit meanings in that field are part of any client API contract. As future-proofing, define the SQL API to not assume that properties that are currently AM-wide or index-wide will remain so unless they logically must be; instead, expose them only when inquiring about a specific index or even specific index column. Also provide the ability for an index AM to override the behavior. In passing, document pg_am.amtype, overlooked in commit 473b93287. Andrew Gierth, with kibitzing by me and others Discussion: <87mvl5on7n.fsf@news-spur.riddles.org.uk>
2016-08-14 00:31:14 +02:00
/*
* Properties for amproperty API. This list covers properties known to the
* core code, but an index AM can define its own properties, by matching the
* string property name.
*/
typedef enum IndexAMProperty
{
AMPROP_UNKNOWN = 0, /* anything not known to core code */
AMPROP_ASC, /* column properties */
AMPROP_DESC,
AMPROP_NULLS_FIRST,
AMPROP_NULLS_LAST,
AMPROP_ORDERABLE,
AMPROP_DISTANCE_ORDERABLE,
AMPROP_RETURNABLE,
AMPROP_SEARCH_ARRAY,
AMPROP_SEARCH_NULLS,
AMPROP_CLUSTERABLE, /* index properties */
AMPROP_INDEX_SCAN,
AMPROP_BITMAP_SCAN,
AMPROP_BACKWARD_SCAN,
AMPROP_CAN_ORDER, /* AM properties */
AMPROP_CAN_UNIQUE,
AMPROP_CAN_MULTI_COL,
Support index INCLUDE in the AM properties interface. This rectifies an oversight in commit 8224de4f4, by adding a new property 'can_include' for pg_indexam_has_property, and adjusting the results of pg_index_column_has_property to give more appropriate results for INCLUDEd columns.
2018-04-08 07:02:05 +02:00
AMPROP_CAN_EXCLUDE,
AMPROP_CAN_INCLUDE,
Add SQL-accessible functions for inspecting index AM properties. Per discussion, we should provide such functions to replace the lost ability to discover AM properties by inspecting pg_am (cf commit 65c5fcd35). The added functionality is also meant to displace any code that was looking directly at pg_index.indoption, since we'd rather not believe that the bit meanings in that field are part of any client API contract. As future-proofing, define the SQL API to not assume that properties that are currently AM-wide or index-wide will remain so unless they logically must be; instead, expose them only when inquiring about a specific index or even specific index column. Also provide the ability for an index AM to override the behavior. In passing, document pg_am.amtype, overlooked in commit 473b93287. Andrew Gierth, with kibitzing by me and others Discussion: <87mvl5on7n.fsf@news-spur.riddles.org.uk>
2016-08-14 00:31:14 +02:00
} IndexAMProperty;
Invent "amadjustmembers" AM method for validating opclass members. This allows AM-specific knowledge to be applied during creation of pg_amop and pg_amproc entries. Specifically, the AM knows better than core code which entries to consider as required or optional. Giving the latter entries the appropriate sort of dependency allows them to be dropped without taking out the whole opclass or opfamily; which is something we'd like to have to correct obsolescent entries in extensions. This callback also opens the door to performing AM-specific validity checks during opclass creation, rather than hoping than an opclass developer will remember to test with "amvalidate". For the most part I've not actually added any such checks yet; that can happen in a follow-on patch. (Note that we shouldn't remove any tests from "amvalidate", as those are still needed to cross-check manually constructed entries in the initdb data. So adding tests to "amadjustmembers" will be somewhat duplicative, but it seems like a good idea anyway.) Patch by me, reviewed by Alexander Korotkov, Hamid Akhtar, and Anastasia Lubennikova. Discussion: https://postgr.es/m/4578.1565195302@sss.pgh.pa.us
2020-08-01 23:12:47 +02:00
/*
* We use lists of this struct type to keep track of both operators and
* support functions while building or adding to an opclass or opfamily.
* amadjustmembers functions receive lists of these structs, and are allowed
* to alter their "ref" fields.
*
* The "ref" fields define how the pg_amop or pg_amproc entry should depend
* on the associated objects (that is, which dependency type to use, and
* which opclass or opfamily it should depend on).
*
* If ref_is_hard is true, the entry will have a NORMAL dependency on the
* operator or support func, and an INTERNAL dependency on the opclass or
* opfamily. This forces the opclass or opfamily to be dropped if the
* operator or support func is dropped, and requires the CASCADE option
* to do so. Nor will ALTER OPERATOR FAMILY DROP be allowed. This is
* the right behavior for objects that are essential to an opclass.
*
* If ref_is_hard is false, the entry will have an AUTO dependency on the
* operator or support func, and also an AUTO dependency on the opclass or
* opfamily. This allows ALTER OPERATOR FAMILY DROP, and causes that to
* happen automatically if the operator or support func is dropped. This
* is the right behavior for inessential ("loose") objects.
*/
typedef struct OpFamilyMember
{
bool is_func; /* is this an operator, or support func? */
Oid object; /* operator or support func's OID */
int number; /* strategy or support func number */
Oid lefttype; /* lefttype */
Oid righttype; /* righttype */
Oid sortfamily; /* ordering operator's sort opfamily, or 0 */
bool ref_is_hard; /* hard or soft dependency? */
bool ref_is_family; /* is dependency on opclass or opfamily? */
Oid refobjid; /* OID of opclass or opfamily */
} OpFamilyMember;
Add SQL-accessible functions for inspecting index AM properties. Per discussion, we should provide such functions to replace the lost ability to discover AM properties by inspecting pg_am (cf commit 65c5fcd35). The added functionality is also meant to displace any code that was looking directly at pg_index.indoption, since we'd rather not believe that the bit meanings in that field are part of any client API contract. As future-proofing, define the SQL API to not assume that properties that are currently AM-wide or index-wide will remain so unless they logically must be; instead, expose them only when inquiring about a specific index or even specific index column. Also provide the ability for an index AM to override the behavior. In passing, document pg_am.amtype, overlooked in commit 473b93287. Andrew Gierth, with kibitzing by me and others Discussion: <87mvl5on7n.fsf@news-spur.riddles.org.uk>
2016-08-14 00:31:14 +02:00
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
/*
* Callback function signatures --- see indexam.sgml for more info.
*/
/* build new index */
typedef IndexBuildResult *(*ambuild_function) (Relation heapRelation,
Relation indexRelation,
struct IndexInfo *indexInfo);
/* build empty index */
typedef void (*ambuildempty_function) (Relation indexRelation);
/* insert this tuple */
typedef bool (*aminsert_function) (Relation indexRelation,
Datum *values,
bool *isnull,
ItemPointer heap_tid,
Relation heapRelation,
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
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,
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
struct IndexInfo *indexInfo);
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
Reuse BrinDesc and BrinRevmap in brininsert The brininsert code used to initialize (and destroy) BrinDesc and BrinRevmap for each tuple, which is not free. This patch initializes these structures only once, and reuses them for all inserts in the same command. The data is passed through indexInfo->ii_AmCache. This also introduces an optional AM callback "aminsertcleanup" that allows performing custom cleanup in case simply pfree-ing ii_AmCache is not sufficient (which is the case when the cache contains TupleDesc, Buffers, and so on). Author: Soumyadeep Chakraborty Reviewed-by: Alvaro Herrera, Matthias van de Meent, Tomas Vondra Discussion: https://postgr.es/m/CAE-ML%2B9r2%3DaO1wwji1sBN9gvPz2xRAtFUGfnffpd0ZqyuzjamA%40mail.gmail.com
2023-11-25 20:27:04 +01:00
/* cleanup after insert */
typedef void (*aminsertcleanup_function) (struct IndexInfo *indexInfo);
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
/* bulk delete */
typedef IndexBulkDeleteResult *(*ambulkdelete_function) (IndexVacuumInfo *info,
IndexBulkDeleteResult *stats,
IndexBulkDeleteCallback callback,
void *callback_state);
/* post-VACUUM cleanup */
typedef IndexBulkDeleteResult *(*amvacuumcleanup_function) (IndexVacuumInfo *info,
IndexBulkDeleteResult *stats);
/* can indexscan return IndexTuples? */
typedef bool (*amcanreturn_function) (Relation indexRelation, int attno);
/* estimate cost of an indexscan */
typedef void (*amcostestimate_function) (struct PlannerInfo *root,
struct IndexPath *path,
double loop_count,
Cost *indexStartupCost,
Cost *indexTotalCost,
Selectivity *indexSelectivity,
Add optimizer and executor support for parallel index scans. In combination with 569174f1be92be93f5366212cc46960d28a5c5cd, which taught the btree AM how to perform parallel index scans, this allows parallel index scan plans on btree indexes. This infrastructure should be general enough to support parallel index scans for other index AMs as well, if someone updates them to support parallel scans. Amit Kapila, reviewed and tested by Anastasia Lubennikova, Tushar Ahuja, and Haribabu Kommi, and me.
2017-02-15 19:53:24 +01:00
double *indexCorrelation,
double *indexPages);
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
/* parse index reloptions */
typedef bytea *(*amoptions_function) (Datum reloptions,
bool validate);
Add SQL-accessible functions for inspecting index AM properties. Per discussion, we should provide such functions to replace the lost ability to discover AM properties by inspecting pg_am (cf commit 65c5fcd35). The added functionality is also meant to displace any code that was looking directly at pg_index.indoption, since we'd rather not believe that the bit meanings in that field are part of any client API contract. As future-proofing, define the SQL API to not assume that properties that are currently AM-wide or index-wide will remain so unless they logically must be; instead, expose them only when inquiring about a specific index or even specific index column. Also provide the ability for an index AM to override the behavior. In passing, document pg_am.amtype, overlooked in commit 473b93287. Andrew Gierth, with kibitzing by me and others Discussion: <87mvl5on7n.fsf@news-spur.riddles.org.uk>
2016-08-14 00:31:14 +02:00
/* report AM, index, or index column property */
typedef bool (*amproperty_function) (Oid index_oid, int attno,
IndexAMProperty prop, const char *propname,
bool *res, bool *isnull);
Report progress of CREATE INDEX operations This uses the progress reporting infrastructure added by c16dc1aca5e0, adding support for CREATE INDEX and CREATE INDEX CONCURRENTLY. There are two pieces to this: one is index-AM-agnostic, and the other is AM-specific. The latter is fairly elaborate for btrees, including reportage for parallel index builds and the separate phases that btree index creation uses; other index AMs, which are much simpler in their building procedures, have simplistic reporting only, but that seems sufficient, at least for non-concurrent builds. The index-AM-agnostic part is fairly complete, providing insight into the CONCURRENTLY wait phases as well as block-based progress during the index validation table scan. (The index validation index scan requires patching each AM, which has not been included here.) Reviewers: Rahila Syed, Pavan Deolasee, Tatsuro Yamada Discussion: https://postgr.es/m/20181220220022.mg63bhk26zdpvmcj@alvherre.pgsql
2019-04-02 20:18:08 +02:00
/* name of phase as used in progress reporting */
typedef char *(*ambuildphasename_function) (int64 phasenum);
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
/* validate definition of an opclass for this AM */
typedef bool (*amvalidate_function) (Oid opclassoid);
Invent "amadjustmembers" AM method for validating opclass members. This allows AM-specific knowledge to be applied during creation of pg_amop and pg_amproc entries. Specifically, the AM knows better than core code which entries to consider as required or optional. Giving the latter entries the appropriate sort of dependency allows them to be dropped without taking out the whole opclass or opfamily; which is something we'd like to have to correct obsolescent entries in extensions. This callback also opens the door to performing AM-specific validity checks during opclass creation, rather than hoping than an opclass developer will remember to test with "amvalidate". For the most part I've not actually added any such checks yet; that can happen in a follow-on patch. (Note that we shouldn't remove any tests from "amvalidate", as those are still needed to cross-check manually constructed entries in the initdb data. So adding tests to "amadjustmembers" will be somewhat duplicative, but it seems like a good idea anyway.) Patch by me, reviewed by Alexander Korotkov, Hamid Akhtar, and Anastasia Lubennikova. Discussion: https://postgr.es/m/4578.1565195302@sss.pgh.pa.us
2020-08-01 23:12:47 +02:00
/* validate operators and support functions to be added to an opclass/family */
typedef void (*amadjustmembers_function) (Oid opfamilyoid,
Oid opclassoid,
List *operators,
List *functions);
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
/* prepare for index scan */
typedef IndexScanDesc (*ambeginscan_function) (Relation indexRelation,
int nkeys,
int norderbys);
/* (re)start index scan */
typedef void (*amrescan_function) (IndexScanDesc scan,
ScanKey keys,
int nkeys,
ScanKey orderbys,
int norderbys);
/* next valid tuple */
typedef bool (*amgettuple_function) (IndexScanDesc scan,
ScanDirection direction);
/* fetch all valid tuples */
typedef int64 (*amgetbitmap_function) (IndexScanDesc scan,
TIDBitmap *tbm);
/* end index scan */
typedef void (*amendscan_function) (IndexScanDesc scan);
/* mark current scan position */
typedef void (*ammarkpos_function) (IndexScanDesc scan);
/* restore marked scan position */
typedef void (*amrestrpos_function) (IndexScanDesc scan);
Extend index AM API for parallel index scans. This patch doesn't actually make any index AM parallel-aware, but it provides the necessary functions at the AM layer to do so. Rahila Syed, Amit Kapila, Robert Haas
2017-01-24 22:42:58 +01:00
/*
* Callback function signatures - for parallel index scans.
*/
/* estimate size of parallel scan descriptor */
typedef Size (*amestimateparallelscan_function) (void);
/* prepare for parallel index scan */
typedef void (*aminitparallelscan_function) (void *target);
/* (re)start parallel index scan */
typedef void (*amparallelrescan_function) (IndexScanDesc scan);
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
/*
* API struct for an index AM. Note this must be stored in a single palloc'd
* chunk of memory.
*/
typedef struct IndexAmRoutine
{
NodeTag type;
/*
* Total number of strategies (operators) by which we can traverse/search
* this AM. Zero if AM does not have a fixed set of strategy assignments.
*/
uint16 amstrategies;
/* total number of support functions that this AM uses */
uint16 amsupport;
Implement operator class parameters PostgreSQL provides set of template index access methods, where opclasses have much freedom in the semantics of indexing. These index AMs are GiST, GIN, SP-GiST and BRIN. There opclasses define representation of keys, operations on them and supported search strategies. So, it's natural that opclasses may be faced some tradeoffs, which require user-side decision. This commit implements opclass parameters allowing users to set some values, which tell opclass how to index the particular dataset. This commit doesn't introduce new storage in system catalog. Instead it uses pg_attribute.attoptions, which is used for table column storage options but unused for index attributes. In order to evade changing signature of each opclass support function, we implement unified way to pass options to opclass support functions. Options are set to fn_expr as the constant bytea expression. It's possible due to the fact that opclass support functions are executed outside of expressions, so fn_expr is unused for them. This commit comes with some examples of opclass options usage. We parametrize signature length in GiST. That applies to multiple opclasses: tsvector_ops, gist__intbig_ops, gist_ltree_ops, gist__ltree_ops, gist_trgm_ops and gist_hstore_ops. Also we parametrize maximum number of integer ranges for gist__int_ops. However, the main future usage of this feature is expected to be json, where users would be able to specify which way to index particular json parts. Catversion is bumped. Discussion: https://postgr.es/m/d22c3a18-31c7-1879-fc11-4c1ce2f5e5af%40postgrespro.ru Author: Nikita Glukhov, revised by me Reviwed-by: Nikolay Shaplov, Robert Haas, Tom Lane, Tomas Vondra, Alvaro Herrera
2020-03-30 18:17:11 +02:00
/* opclass options support function number or 0 */
uint16 amoptsprocnum;
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
/* does AM support ORDER BY indexed column's value? */
bool amcanorder;
/* does AM support ORDER BY result of an operator on indexed column? */
bool amcanorderbyop;
/* does AM support backward scanning? */
bool amcanbackward;
/* does AM support UNIQUE indexes? */
bool amcanunique;
/* does AM support multi-column indexes? */
bool amcanmulticol;
/* does AM require scans to have a constraint on the first index column? */
bool amoptionalkey;
/* does AM handle ScalarArrayOpExpr quals? */
bool amsearcharray;
/* does AM handle IS NULL/IS NOT NULL quals? */
bool amsearchnulls;
/* can index storage data type differ from column data type? */
bool amstorage;
/* can an index of this type be clustered on? */
bool amclusterable;
/* does AM handle predicate locks? */
bool ampredlocks;
Add optimizer and executor support for parallel index scans. In combination with 569174f1be92be93f5366212cc46960d28a5c5cd, which taught the btree AM how to perform parallel index scans, this allows parallel index scan plans on btree indexes. This infrastructure should be general enough to support parallel index scans for other index AMs as well, if someone updates them to support parallel scans. Amit Kapila, reviewed and tested by Anastasia Lubennikova, Tushar Ahuja, and Haribabu Kommi, and me.
2017-02-15 19:53:24 +01:00
/* does AM support parallel scan? */
bool amcanparallel;
Allow parallel CREATE INDEX for BRIN indexes Allow using multiple worker processes to build BRIN index, which until now was supported only for BTREE indexes. For large tables this often results in significant speedup when the build is CPU-bound. The work is split in a simple way - each worker builds BRIN summaries on a subset of the table, determined by the regular parallel scan used to read the data, and feeds them into a shared tuplesort which sorts them by blkno (start of the range). The leader then reads this sorted stream of ranges, merges duplicates (which may happen if the parallel scan does not align with BRIN pages_per_range), and adds the resulting ranges into the index. The number of duplicate results produced by workers (requiring merging in the leader process) should be fairly small, thanks to how parallel scans assign chunks to workers. The likelihood of duplicate results may increase for higher pages_per_range values, but then there are fewer page ranges in total. In any case, we expect the merging to be much cheaper than summarization, so this should be a win. Most of the parallelism infrastructure is a simplified copy of the code used by BTREE indexes, omitting the parts irrelevant for BRIN indexes (e.g. uniqueness checks). This also introduces a new index AM flag amcanbuildparallel, determining whether to attempt to start parallel workers for the index build. Original patch by me, with reviews and substantial reworks by Matthias van de Meent, certainly enough to make him a co-author. Author: Tomas Vondra, Matthias van de Meent Reviewed-by: Matthias van de Meent Discussion: https://postgr.es/m/c2ee7d69-ce17-43f2-d1a0-9811edbda6e6%40enterprisedb.com
2023-12-08 18:15:23 +01:00
/* does AM support parallel build? */
bool amcanbuildparallel;
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
/* does AM support columns included with clause INCLUDE? */
bool amcaninclude;
Introduce IndexAM fields for parallel vacuum. Introduce new fields amusemaintenanceworkmem and amparallelvacuumoptions in IndexAmRoutine for parallel vacuum. The amusemaintenanceworkmem tells whether a particular IndexAM uses maintenance_work_mem or not. This will help in controlling the memory used by individual workers as otherwise, each worker can consume memory equal to maintenance_work_mem. The amparallelvacuumoptions tell whether a particular IndexAM participates in a parallel vacuum and if so in which phase (bulkdelete, vacuumcleanup) of vacuum. Author: Masahiko Sawada and Amit Kapila Reviewed-by: Dilip Kumar, Amit Kapila, Tomas Vondra and Robert Haas Discussion: https://postgr.es/m/CAD21AoDTPMgzSkV4E3SFo1CH_x50bf5PqZFQf4jmqjk-C03BWg@mail.gmail.com https://postgr.es/m/CAA4eK1LmcD5aPogzwim5Nn58Ki+74a6Edghx4Wd8hAskvHaq5A@mail.gmail.com
2020-01-15 02:54:14 +01:00
/* does AM use maintenance_work_mem? */
bool amusemaintenanceworkmem;
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
/* does AM store tuple information only at block granularity? */
bool amsummarizing;
Introduce IndexAM fields for parallel vacuum. Introduce new fields amusemaintenanceworkmem and amparallelvacuumoptions in IndexAmRoutine for parallel vacuum. The amusemaintenanceworkmem tells whether a particular IndexAM uses maintenance_work_mem or not. This will help in controlling the memory used by individual workers as otherwise, each worker can consume memory equal to maintenance_work_mem. The amparallelvacuumoptions tell whether a particular IndexAM participates in a parallel vacuum and if so in which phase (bulkdelete, vacuumcleanup) of vacuum. Author: Masahiko Sawada and Amit Kapila Reviewed-by: Dilip Kumar, Amit Kapila, Tomas Vondra and Robert Haas Discussion: https://postgr.es/m/CAD21AoDTPMgzSkV4E3SFo1CH_x50bf5PqZFQf4jmqjk-C03BWg@mail.gmail.com https://postgr.es/m/CAA4eK1LmcD5aPogzwim5Nn58Ki+74a6Edghx4Wd8hAskvHaq5A@mail.gmail.com
2020-01-15 02:54:14 +01:00
/* OR of parallel vacuum flags. See vacuum.h for flags. */
uint8 amparallelvacuumoptions;
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
/* type of data stored in index, or InvalidOid if variable */
Oid amkeytype;
Support index INCLUDE in the AM properties interface. This rectifies an oversight in commit 8224de4f4, by adding a new property 'can_include' for pg_indexam_has_property, and adjusting the results of pg_index_column_has_property to give more appropriate results for INCLUDEd columns.
2018-04-08 07:02:05 +02:00
/*
* If you add new properties to either the above or the below lists, then
* they should also (usually) be exposed via the property API (see
* IndexAMProperty at the top of the file, and utils/adt/amutils.c).
*/
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
/* interface functions */
ambuild_function ambuild;
ambuildempty_function ambuildempty;
aminsert_function aminsert;
Reuse BrinDesc and BrinRevmap in brininsert The brininsert code used to initialize (and destroy) BrinDesc and BrinRevmap for each tuple, which is not free. This patch initializes these structures only once, and reuses them for all inserts in the same command. The data is passed through indexInfo->ii_AmCache. This also introduces an optional AM callback "aminsertcleanup" that allows performing custom cleanup in case simply pfree-ing ii_AmCache is not sufficient (which is the case when the cache contains TupleDesc, Buffers, and so on). Author: Soumyadeep Chakraborty Reviewed-by: Alvaro Herrera, Matthias van de Meent, Tomas Vondra Discussion: https://postgr.es/m/CAE-ML%2B9r2%3DaO1wwji1sBN9gvPz2xRAtFUGfnffpd0ZqyuzjamA%40mail.gmail.com
2023-11-25 20:27:04 +01:00
aminsertcleanup_function aminsertcleanup;
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
ambulkdelete_function ambulkdelete;
amvacuumcleanup_function amvacuumcleanup;
amcanreturn_function amcanreturn; /* can be NULL */
amcostestimate_function amcostestimate;
amoptions_function amoptions;
Add SQL-accessible functions for inspecting index AM properties. Per discussion, we should provide such functions to replace the lost ability to discover AM properties by inspecting pg_am (cf commit 65c5fcd35). The added functionality is also meant to displace any code that was looking directly at pg_index.indoption, since we'd rather not believe that the bit meanings in that field are part of any client API contract. As future-proofing, define the SQL API to not assume that properties that are currently AM-wide or index-wide will remain so unless they logically must be; instead, expose them only when inquiring about a specific index or even specific index column. Also provide the ability for an index AM to override the behavior. In passing, document pg_am.amtype, overlooked in commit 473b93287. Andrew Gierth, with kibitzing by me and others Discussion: <87mvl5on7n.fsf@news-spur.riddles.org.uk>
2016-08-14 00:31:14 +02:00
amproperty_function amproperty; /* can be NULL */
Report progress of CREATE INDEX operations This uses the progress reporting infrastructure added by c16dc1aca5e0, adding support for CREATE INDEX and CREATE INDEX CONCURRENTLY. There are two pieces to this: one is index-AM-agnostic, and the other is AM-specific. The latter is fairly elaborate for btrees, including reportage for parallel index builds and the separate phases that btree index creation uses; other index AMs, which are much simpler in their building procedures, have simplistic reporting only, but that seems sufficient, at least for non-concurrent builds. The index-AM-agnostic part is fairly complete, providing insight into the CONCURRENTLY wait phases as well as block-based progress during the index validation table scan. (The index validation index scan requires patching each AM, which has not been included here.) Reviewers: Rahila Syed, Pavan Deolasee, Tatsuro Yamada Discussion: https://postgr.es/m/20181220220022.mg63bhk26zdpvmcj@alvherre.pgsql
2019-04-02 20:18:08 +02:00
ambuildphasename_function ambuildphasename; /* can be NULL */
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
amvalidate_function amvalidate;
Invent "amadjustmembers" AM method for validating opclass members. This allows AM-specific knowledge to be applied during creation of pg_amop and pg_amproc entries. Specifically, the AM knows better than core code which entries to consider as required or optional. Giving the latter entries the appropriate sort of dependency allows them to be dropped without taking out the whole opclass or opfamily; which is something we'd like to have to correct obsolescent entries in extensions. This callback also opens the door to performing AM-specific validity checks during opclass creation, rather than hoping than an opclass developer will remember to test with "amvalidate". For the most part I've not actually added any such checks yet; that can happen in a follow-on patch. (Note that we shouldn't remove any tests from "amvalidate", as those are still needed to cross-check manually constructed entries in the initdb data. So adding tests to "amadjustmembers" will be somewhat duplicative, but it seems like a good idea anyway.) Patch by me, reviewed by Alexander Korotkov, Hamid Akhtar, and Anastasia Lubennikova. Discussion: https://postgr.es/m/4578.1565195302@sss.pgh.pa.us
2020-08-01 23:12:47 +02:00
amadjustmembers_function amadjustmembers; /* can be NULL */
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
ambeginscan_function ambeginscan;
amrescan_function amrescan;
amgettuple_function amgettuple; /* can be NULL */
amgetbitmap_function amgetbitmap; /* can be NULL */
amendscan_function amendscan;
ammarkpos_function ammarkpos; /* can be NULL */
amrestrpos_function amrestrpos; /* can be NULL */
Extend index AM API for parallel index scans. This patch doesn't actually make any index AM parallel-aware, but it provides the necessary functions at the AM layer to do so. Rahila Syed, Amit Kapila, Robert Haas
2017-01-24 22:42:58 +01:00
/* interface functions to support parallel index scans */
amestimateparallelscan_function amestimateparallelscan; /* can be NULL */
aminitparallelscan_function aminitparallelscan; /* can be NULL */
amparallelrescan_function amparallelrescan; /* can be NULL */
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
} IndexAmRoutine;
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
/* Functions in access/index/amapi.c */
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
extern IndexAmRoutine *GetIndexAmRoutine(Oid amhandler);
Add SQL-accessible functions for inspecting index AM properties. Per discussion, we should provide such functions to replace the lost ability to discover AM properties by inspecting pg_am (cf commit 65c5fcd35). The added functionality is also meant to displace any code that was looking directly at pg_index.indoption, since we'd rather not believe that the bit meanings in that field are part of any client API contract. As future-proofing, define the SQL API to not assume that properties that are currently AM-wide or index-wide will remain so unless they logically must be; instead, expose them only when inquiring about a specific index or even specific index column. Also provide the ability for an index AM to override the behavior. In passing, document pg_am.amtype, overlooked in commit 473b93287. Andrew Gierth, with kibitzing by me and others Discussion: <87mvl5on7n.fsf@news-spur.riddles.org.uk>
2016-08-14 00:31:14 +02:00
extern IndexAmRoutine *GetIndexAmRoutineByAmId(Oid amoid, bool noerror);
Restructure index access method API to hide most of it at the C level. This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
2016-01-18 01:36:59 +01:00
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
#endif /* AMAPI_H */