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postgresql/src/include/executor/tuptable.h

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Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
/*-------------------------------------------------------------------------
*
Change my-function-name-- to my_function_name, and optimizer renames.
1999-02-14 00:22:53 +01:00
* tuptable.h
Massive commit to run PGINDENT on all *.c and *.h files.
1997-09-07 07:04:48 +02:00
* tuple table support stuff
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
*
*
Update copyright for 2018 Backpatch-through: certain files through 9.3
2018-01-03 05:30:12 +01:00
* Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group
Add: * Portions Copyright (c) 1996-2000, PostgreSQL, Inc to all files copyright Regents of Berkeley. Man, that's a lot of files.
2000-01-26 06:58:53 +01:00
* Portions Copyright (c) 1994, Regents of the University of California
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
*
Remove cvs keywords from all files.
2010-09-20 22:08:53 +02:00
* src/include/executor/tuptable.h
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
*
*-------------------------------------------------------------------------
*/
#ifndef TUPTABLE_H
#define TUPTABLE_H
Change #include's to use <> and "" as appropriate.
1999-07-16 01:04:24 +02:00
#include "access/htup.h"
Split tuple struct defs from htup.h to htup_details.h This reduces unnecessary exposure of other headers through htup.h, which is very widely included by many files. I have chosen to move the function prototypes to the new file as well, because that means htup.h no longer needs to include tupdesc.h. In itself this doesn't have much effect in indirect inclusion of tupdesc.h throughout the tree, because it's also required by execnodes.h; but it's something to explore in the future, and it seemed best to do the htup.h change now while I'm busy with it.
2012-08-30 22:15:44 +02:00
#include "access/tupdesc.h"
More include file adjustments.
2006-07-13 19:47:02 +02:00
#include "storage/buf.h"
Avoid O(N^2) overhead in repeated nocachegetattr calls when columns of a tuple are being accessed via ExecEvalVar and the attcacheoff shortcut isn't usable (due to nulls and/or varlena columns). To do this, cache Datums extracted from a tuple in the associated TupleTableSlot. Also some code cleanup in and around the TupleTable handling. Atsushi Ogawa with some kibitzing by Tom Lane.
2005-03-14 05:41:13 +01:00
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
/*----------
Replace the array-style TupleTable data structure with a simple List of TupleTableSlot nodes. This eliminates the need to count in advance how many Slots will be needed, which seems more than worth the small increase in the amount of palloc traffic during executor startup. The ExecCountSlots infrastructure is now all dead code, but I'll remove it in a separate commit for clarity. Per a comment from Robert Haas.
2009-09-27 22:09:58 +02:00
* The executor stores tuples in a "tuple table" which is a List of
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
* independent TupleTableSlots. There are several cases we need to handle:
* 1. physical tuple in a disk buffer page
* 2. physical tuple constructed in palloc'ed memory
Create infrastructure for 'MinimalTuple' representation of in-memory tuples with less header overhead than a regular HeapTuple, per my recent proposal. Teach TupleTableSlot code how to deal with these. As proof of concept, change tuplestore.c to store MinimalTuples instead of HeapTuples. Future patches will expand the concept to other places where it is useful.
2006-06-27 04:51:40 +02:00
* 3. "minimal" physical tuple constructed in palloc'ed memory
* 4. "virtual" tuple consisting of Datum/isnull arrays
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
*
* The first two cases are similar in that they both deal with "materialized"
* tuples, but resource management is different. For a tuple in a disk page
* we need to hold a pin on the buffer until the TupleTableSlot's reference
* to the tuple is dropped; while for a palloc'd tuple we usually want the
* tuple pfree'd when the TupleTableSlot's reference is dropped.
*
Create infrastructure for 'MinimalTuple' representation of in-memory tuples with less header overhead than a regular HeapTuple, per my recent proposal. Teach TupleTableSlot code how to deal with these. As proof of concept, change tuplestore.c to store MinimalTuples instead of HeapTuples. Future patches will expand the concept to other places where it is useful.
2006-06-27 04:51:40 +02:00
* A "minimal" tuple is handled similarly to a palloc'd regular tuple.
* At present, minimal tuples never are stored in buffers, so there is no
pgindent run for 9.4 This includes removing tabs after periods in C comments, which was applied to back branches, so this change should not effect backpatching.
2014-05-06 18:12:18 +02:00
* parallel to case 1. Note that a minimal tuple has no "system columns".
Create infrastructure for 'MinimalTuple' representation of in-memory tuples with less header overhead than a regular HeapTuple, per my recent proposal. Teach TupleTableSlot code how to deal with these. As proof of concept, change tuplestore.c to store MinimalTuples instead of HeapTuples. Future patches will expand the concept to other places where it is useful.
2006-06-27 04:51:40 +02:00
* (Actually, it could have an OID, but we have no need to access the OID.)
*
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
* A "virtual" tuple is an optimization used to minimize physical data
* copying in a nest of plan nodes. Any pass-by-reference Datums in the
* tuple point to storage that is not directly associated with the
* TupleTableSlot; generally they will point to part of a tuple stored in
* a lower plan node's output TupleTableSlot, or to a function result
* constructed in a plan node's per-tuple econtext. It is the responsibility
* of the generating plan node to be sure these resources are not released
pgindent run for 9.4 This includes removing tabs after periods in C comments, which was applied to back branches, so this change should not effect backpatching.
2014-05-06 18:12:18 +02:00
* for as long as the virtual tuple needs to be valid. We only use virtual
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
* tuples in the result slots of plan nodes --- tuples to be copied anywhere
* else need to be "materialized" into physical tuples. Note also that a
* virtual tuple does not have any "system columns".
*
Fix an oversight in the support for storing/retrieving "minimal tuples" in TupleTableSlots. We have functions for retrieving a minimal tuple from a slot after storing a regular tuple in it, or vice versa; but these were implemented by converting the internal storage from one format to the other. The problem with that is it invalidates any pass-by-reference Datums that were already fetched from the slot, since they'll be pointing into the just-freed version of the tuple. The known problem cases involve fetching both a whole-row variable and a pass-by-reference value from a slot that is fed from a tuplestore or tuplesort object. The added regression tests illustrate some simple cases, but there may be other failure scenarios traceable to the same bug. Note that the added tests probably only fail on unpatched code if it's built with --enable-cassert; otherwise the bug leads to fetching from freed memory, which will not have been overwritten without additional conditions. Fix by allowing a slot to contain both formats simultaneously; which turns out not to complicate the logic much at all, if anything it seems less contorted than before. Back-patch to 8.2, where minimal tuples were introduced.
2009-03-30 06:08:43 +02:00
* It is also possible for a TupleTableSlot to hold both physical and minimal
* copies of a tuple. This is done when the slot is requested to provide
* the format other than the one it currently holds. (Originally we attempted
* to handle such requests by replacing one format with the other, but that
* had the fatal defect of invalidating any pass-by-reference Datums pointing
* into the existing slot contents.) Both copies must contain identical data
* payloads when this is the case.
*
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
* The Datum/isnull arrays of a TupleTableSlot serve double duty. When the
pgindent run for 9.4 This includes removing tabs after periods in C comments, which was applied to back branches, so this change should not effect backpatching.
2014-05-06 18:12:18 +02:00
* slot contains a virtual tuple, they are the authoritative data. When the
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
* slot contains a physical tuple, the arrays contain data extracted from
* the tuple. (In this state, any pass-by-reference Datums point into
* the physical tuple.) The extracted information is built "lazily",
pgindent run for 9.4 This includes removing tabs after periods in C comments, which was applied to back branches, so this change should not effect backpatching.
2014-05-06 18:12:18 +02:00
* ie, only as needed. This serves to avoid repeated extraction of data
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
* from the physical tuple.
*
Move TupleTableSlots boolean member into one flag variable. There's several reasons for this change: 1) It reduces the total size of TupleTableSlot / reduces alignment padding, making the commonly accessed members fit into a single cacheline (but we currently do not force proper alignment, so that's not yet guaranteed to be helpful) 2) Combining the booleans into a flag allows to combine read/writes from memory. 3) With the upcoming slot abstraction changes, it allows to have core and extended flags, in a memory efficient way. Author: Ashutosh Bapat and Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-10-16 00:24:33 +02:00
* A TupleTableSlot can also be "empty", indicated by flag TTS_EMPTY set in
* tts_flags, holding no valid data. This is the only valid state for a
* freshly-created slot that has not yet had a tuple descriptor assigned to it.
* In this state, TTS_SHOULDFREE should not be set in tts_flag, tts_tuple must
* be NULL, tts_buffer InvalidBuffer, and tts_nvalid zero.
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
*
Fix problems with cached tuple descriptors disappearing while still in use by creating a reference-count mechanism, similar to what we did a long time ago for catcache entries. The back branches have an ugly solution involving lots of extra copies, but this way is more efficient. Reference counting is only applied to tupdescs that are actually in caches --- there seems no need to use it for tupdescs that are generated in the executor, since they'll go away during plan shutdown by virtue of being in the per-query memory context. Neil Conway and Tom Lane
2006-06-16 20:42:24 +02:00
* The tupleDescriptor is simply referenced, not copied, by the TupleTableSlot
* code. The caller of ExecSetSlotDescriptor() is responsible for providing
* a descriptor that will live as long as the slot does. (Typically, both
* slots and descriptors are in per-query memory and are freed by memory
* context deallocation at query end; so it's not worth providing any extra
* mechanism to do more. However, the slot will increment the tupdesc
* reference count if a reference-counted tupdesc is supplied.)
*
Move TupleTableSlots boolean member into one flag variable. There's several reasons for this change: 1) It reduces the total size of TupleTableSlot / reduces alignment padding, making the commonly accessed members fit into a single cacheline (but we currently do not force proper alignment, so that's not yet guaranteed to be helpful) 2) Combining the booleans into a flag allows to combine read/writes from memory. 3) With the upcoming slot abstraction changes, it allows to have core and extended flags, in a memory efficient way. Author: Ashutosh Bapat and Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-10-16 00:24:33 +02:00
* When TTS_SHOULDFREE is set in tts_flags, the physical tuple is "owned" by
* the slot and should be freed when the slot's reference to the tuple is
* dropped.
Fix typos in comments.
1999-02-23 08:36:31 +01:00
*
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
* If tts_buffer is not InvalidBuffer, then the slot is holding a pin
Avoid O(N^2) overhead in repeated nocachegetattr calls when columns of a tuple are being accessed via ExecEvalVar and the attcacheoff shortcut isn't usable (due to nulls and/or varlena columns). To do this, cache Datums extracted from a tuple in the associated TupleTableSlot. Also some code cleanup in and around the TupleTable handling. Atsushi Ogawa with some kibitzing by Tom Lane.
2005-03-14 05:41:13 +01:00
* on the indicated buffer page; drop the pin when we release the
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
* slot's reference to that buffer. (tts_shouldFree should always be
* false in such a case, since presumably tts_tuple is pointing at the
Avoid O(N^2) overhead in repeated nocachegetattr calls when columns of a tuple are being accessed via ExecEvalVar and the attcacheoff shortcut isn't usable (due to nulls and/or varlena columns). To do this, cache Datums extracted from a tuple in the associated TupleTableSlot. Also some code cleanup in and around the TupleTable handling. Atsushi Ogawa with some kibitzing by Tom Lane.
2005-03-14 05:41:13 +01:00
* buffer page.)
Fix typos in comments.
1999-02-23 08:36:31 +01:00
*
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
* tts_nvalid indicates the number of valid columns in the tts_values/isnull
pgindent run for 9.4 This includes removing tabs after periods in C comments, which was applied to back branches, so this change should not effect backpatching.
2014-05-06 18:12:18 +02:00
* arrays. When the slot is holding a "virtual" tuple this must be equal
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
* to the descriptor's natts. When the slot is holding a physical tuple
* this is equal to the number of columns we have extracted (we always
* extract columns from left to right, so there are no holes).
*
* tts_values/tts_isnull are allocated when a descriptor is assigned to the
* slot; they are of length equal to the descriptor's natts.
*
Create infrastructure for 'MinimalTuple' representation of in-memory tuples with less header overhead than a regular HeapTuple, per my recent proposal. Teach TupleTableSlot code how to deal with these. As proof of concept, change tuplestore.c to store MinimalTuples instead of HeapTuples. Future patches will expand the concept to other places where it is useful.
2006-06-27 04:51:40 +02:00
* tts_mintuple must always be NULL if the slot does not hold a "minimal"
* tuple. When it does, tts_mintuple points to the actual MinimalTupleData
Fix an oversight in the support for storing/retrieving "minimal tuples" in TupleTableSlots. We have functions for retrieving a minimal tuple from a slot after storing a regular tuple in it, or vice versa; but these were implemented by converting the internal storage from one format to the other. The problem with that is it invalidates any pass-by-reference Datums that were already fetched from the slot, since they'll be pointing into the just-freed version of the tuple. The known problem cases involve fetching both a whole-row variable and a pass-by-reference value from a slot that is fed from a tuplestore or tuplesort object. The added regression tests illustrate some simple cases, but there may be other failure scenarios traceable to the same bug. Note that the added tests probably only fail on unpatched code if it's built with --enable-cassert; otherwise the bug leads to fetching from freed memory, which will not have been overwritten without additional conditions. Fix by allowing a slot to contain both formats simultaneously; which turns out not to complicate the logic much at all, if anything it seems less contorted than before. Back-patch to 8.2, where minimal tuples were introduced.
2009-03-30 06:08:43 +02:00
* object (the thing to be pfree'd if tts_shouldFreeMin is true). If the slot
* has only a minimal and not also a regular physical tuple, then tts_tuple
* points at tts_minhdr and the fields of that struct are set correctly
Create infrastructure for 'MinimalTuple' representation of in-memory tuples with less header overhead than a regular HeapTuple, per my recent proposal. Teach TupleTableSlot code how to deal with these. As proof of concept, change tuplestore.c to store MinimalTuples instead of HeapTuples. Future patches will expand the concept to other places where it is useful.
2006-06-27 04:51:40 +02:00
* for access to the minimal tuple; in particular, tts_minhdr.t_data points
pgindent run for 9.4 This includes removing tabs after periods in C comments, which was applied to back branches, so this change should not effect backpatching.
2014-05-06 18:12:18 +02:00
* MINIMAL_TUPLE_OFFSET bytes before tts_mintuple. This allows column
Fix an oversight in the support for storing/retrieving "minimal tuples" in TupleTableSlots. We have functions for retrieving a minimal tuple from a slot after storing a regular tuple in it, or vice versa; but these were implemented by converting the internal storage from one format to the other. The problem with that is it invalidates any pass-by-reference Datums that were already fetched from the slot, since they'll be pointing into the just-freed version of the tuple. The known problem cases involve fetching both a whole-row variable and a pass-by-reference value from a slot that is fed from a tuplestore or tuplesort object. The added regression tests illustrate some simple cases, but there may be other failure scenarios traceable to the same bug. Note that the added tests probably only fail on unpatched code if it's built with --enable-cassert; otherwise the bug leads to fetching from freed memory, which will not have been overwritten without additional conditions. Fix by allowing a slot to contain both formats simultaneously; which turns out not to complicate the logic much at all, if anything it seems less contorted than before. Back-patch to 8.2, where minimal tuples were introduced.
2009-03-30 06:08:43 +02:00
* extraction to treat the case identically to regular physical tuples.
Create infrastructure for 'MinimalTuple' representation of in-memory tuples with less header overhead than a regular HeapTuple, per my recent proposal. Teach TupleTableSlot code how to deal with these. As proof of concept, change tuplestore.c to store MinimalTuples instead of HeapTuples. Future patches will expand the concept to other places where it is useful.
2006-06-27 04:51:40 +02:00
*
Move TupleTableSlots boolean member into one flag variable. There's several reasons for this change: 1) It reduces the total size of TupleTableSlot / reduces alignment padding, making the commonly accessed members fit into a single cacheline (but we currently do not force proper alignment, so that's not yet guaranteed to be helpful) 2) Combining the booleans into a flag allows to combine read/writes from memory. 3) With the upcoming slot abstraction changes, it allows to have core and extended flags, in a memory efficient way. Author: Ashutosh Bapat and Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-10-16 00:24:33 +02:00
* TTS_SLOW flag in tts_flags and tts_off are saved state for
* slot_deform_tuple, and should not be touched by any other code.
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
*----------
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
*/
Move TupleTableSlots boolean member into one flag variable. There's several reasons for this change: 1) It reduces the total size of TupleTableSlot / reduces alignment padding, making the commonly accessed members fit into a single cacheline (but we currently do not force proper alignment, so that's not yet guaranteed to be helpful) 2) Combining the booleans into a flag allows to combine read/writes from memory. 3) With the upcoming slot abstraction changes, it allows to have core and extended flags, in a memory efficient way. Author: Ashutosh Bapat and Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-10-16 00:24:33 +02:00
/* true = slot is empty */
#define TTS_FLAG_EMPTY (1 << 1)
#define TTS_EMPTY(slot) (((slot)->tts_flags & TTS_FLAG_EMPTY) != 0)
/* should pfree tts_tuple? */
#define TTS_FLAG_SHOULDFREE (1 << 2)
#define TTS_SHOULDFREE(slot) (((slot)->tts_flags & TTS_FLAG_SHOULDFREE) != 0)
/* should pfree tts_mintuple? */
#define TTS_FLAG_SHOULDFREEMIN (1 << 3)
#define TTS_SHOULDFREEMIN(slot) (((slot)->tts_flags & TTS_FLAG_SHOULDFREEMIN) != 0)
/* saved state for slot_deform_tuple */
#define TTS_FLAG_SLOW (1 << 4)
#define TTS_SLOW(slot) (((slot)->tts_flags & TTS_FLAG_SLOW) != 0)
/* fixed tuple descriptor */
#define TTS_FLAG_FIXED (1 << 5)
#define TTS_FIXED(slot) (((slot)->tts_flags & TTS_FLAG_FIXED) != 0)
Massive commit to run PGINDENT on all *.c and *.h files.
1997-09-07 07:04:48 +02:00
typedef struct TupleTableSlot
{
Replace the array-style TupleTable data structure with a simple List of TupleTableSlot nodes. This eliminates the need to count in advance how many Slots will be needed, which seems more than worth the small increase in the amount of palloc traffic during executor startup. The ExecCountSlots infrastructure is now all dead code, but I'll remove it in a separate commit for clarity. Per a comment from Robert Haas.
2009-09-27 22:09:58 +02:00
NodeTag type;
Move TupleTableSlots boolean member into one flag variable. There's several reasons for this change: 1) It reduces the total size of TupleTableSlot / reduces alignment padding, making the commonly accessed members fit into a single cacheline (but we currently do not force proper alignment, so that's not yet guaranteed to be helpful) 2) Combining the booleans into a flag allows to combine read/writes from memory. 3) With the upcoming slot abstraction changes, it allows to have core and extended flags, in a memory efficient way. Author: Ashutosh Bapat and Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-10-16 00:24:33 +02:00
#define FIELDNO_TUPLETABLESLOT_FLAGS 1
uint16 tts_flags; /* Boolean states */
#define FIELDNO_TUPLETABLESLOT_NVALID 2
AttrNumber tts_nvalid; /* # of valid values in tts_values */
#define FIELDNO_TUPLETABLESLOT_TUPLE 3
Fix an oversight in the support for storing/retrieving "minimal tuples" in TupleTableSlots. We have functions for retrieving a minimal tuple from a slot after storing a regular tuple in it, or vice versa; but these were implemented by converting the internal storage from one format to the other. The problem with that is it invalidates any pass-by-reference Datums that were already fetched from the slot, since they'll be pointing into the just-freed version of the tuple. The known problem cases involve fetching both a whole-row variable and a pass-by-reference value from a slot that is fed from a tuplestore or tuplesort object. The added regression tests illustrate some simple cases, but there may be other failure scenarios traceable to the same bug. Note that the added tests probably only fail on unpatched code if it's built with --enable-cassert; otherwise the bug leads to fetching from freed memory, which will not have been overwritten without additional conditions. Fix by allowing a slot to contain both formats simultaneously; which turns out not to complicate the logic much at all, if anything it seems less contorted than before. Back-patch to 8.2, where minimal tuples were introduced.
2009-03-30 06:08:43 +02:00
HeapTuple tts_tuple; /* physical tuple, or NULL if virtual */
Move TupleTableSlots boolean member into one flag variable. There's several reasons for this change: 1) It reduces the total size of TupleTableSlot / reduces alignment padding, making the commonly accessed members fit into a single cacheline (but we currently do not force proper alignment, so that's not yet guaranteed to be helpful) 2) Combining the booleans into a flag allows to combine read/writes from memory. 3) With the upcoming slot abstraction changes, it allows to have core and extended flags, in a memory efficient way. Author: Ashutosh Bapat and Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-10-16 00:24:33 +02:00
#define FIELDNO_TUPLETABLESLOT_TUPLEDESCRIPTOR 4
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
TupleDesc tts_tupleDescriptor; /* slot's tuple descriptor */
MemoryContext tts_mcxt; /* slot itself is in this context */
Buffer tts_buffer; /* tuple's buffer, or InvalidBuffer */
Move TupleTableSlots boolean member into one flag variable. There's several reasons for this change: 1) It reduces the total size of TupleTableSlot / reduces alignment padding, making the commonly accessed members fit into a single cacheline (but we currently do not force proper alignment, so that's not yet guaranteed to be helpful) 2) Combining the booleans into a flag allows to combine read/writes from memory. 3) With the upcoming slot abstraction changes, it allows to have core and extended flags, in a memory efficient way. Author: Ashutosh Bapat and Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-10-16 00:24:33 +02:00
#define FIELDNO_TUPLETABLESLOT_OFF 7
uint32 tts_off; /* saved state for slot_deform_tuple */
#define FIELDNO_TUPLETABLESLOT_VALUES 8
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
Datum *tts_values; /* current per-attribute values */
Move TupleTableSlots boolean member into one flag variable. There's several reasons for this change: 1) It reduces the total size of TupleTableSlot / reduces alignment padding, making the commonly accessed members fit into a single cacheline (but we currently do not force proper alignment, so that's not yet guaranteed to be helpful) 2) Combining the booleans into a flag allows to combine read/writes from memory. 3) With the upcoming slot abstraction changes, it allows to have core and extended flags, in a memory efficient way. Author: Ashutosh Bapat and Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-10-16 00:24:33 +02:00
#define FIELDNO_TUPLETABLESLOT_ISNULL 9
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
bool *tts_isnull; /* current per-attribute isnull flags */
Fix an oversight in the support for storing/retrieving "minimal tuples" in TupleTableSlots. We have functions for retrieving a minimal tuple from a slot after storing a regular tuple in it, or vice versa; but these were implemented by converting the internal storage from one format to the other. The problem with that is it invalidates any pass-by-reference Datums that were already fetched from the slot, since they'll be pointing into the just-freed version of the tuple. The known problem cases involve fetching both a whole-row variable and a pass-by-reference value from a slot that is fed from a tuplestore or tuplesort object. The added regression tests illustrate some simple cases, but there may be other failure scenarios traceable to the same bug. Note that the added tests probably only fail on unpatched code if it's built with --enable-cassert; otherwise the bug leads to fetching from freed memory, which will not have been overwritten without additional conditions. Fix by allowing a slot to contain both formats simultaneously; which turns out not to complicate the logic much at all, if anything it seems less contorted than before. Back-patch to 8.2, where minimal tuples were introduced.
2009-03-30 06:08:43 +02:00
MinimalTuple tts_mintuple; /* minimal tuple, or NULL if none */
HeapTupleData tts_minhdr; /* workspace for minimal-tuple-only case */
Used modified version of indent that understands over 100 typedefs.
1997-09-08 23:56:23 +02:00
} TupleTableSlot;
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
Fix an oversight in the support for storing/retrieving "minimal tuples" in TupleTableSlots. We have functions for retrieving a minimal tuple from a slot after storing a regular tuple in it, or vice versa; but these were implemented by converting the internal storage from one format to the other. The problem with that is it invalidates any pass-by-reference Datums that were already fetched from the slot, since they'll be pointing into the just-freed version of the tuple. The known problem cases involve fetching both a whole-row variable and a pass-by-reference value from a slot that is fed from a tuplestore or tuplesort object. The added regression tests illustrate some simple cases, but there may be other failure scenarios traceable to the same bug. Note that the added tests probably only fail on unpatched code if it's built with --enable-cassert; otherwise the bug leads to fetching from freed memory, which will not have been overwritten without additional conditions. Fix by allowing a slot to contain both formats simultaneously; which turns out not to complicate the logic much at all, if anything it seems less contorted than before. Back-patch to 8.2, where minimal tuples were introduced.
2009-03-30 06:08:43 +02:00
#define TTS_HAS_PHYSICAL_TUPLE(slot) \
((slot)->tts_tuple != NULL && (slot)->tts_tuple != &((slot)->tts_minhdr))
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
/*
* TupIsNull -- is a TupleTableSlot empty?
*/
#define TupIsNull(slot) \
Move TupleTableSlots boolean member into one flag variable. There's several reasons for this change: 1) It reduces the total size of TupleTableSlot / reduces alignment padding, making the commonly accessed members fit into a single cacheline (but we currently do not force proper alignment, so that's not yet guaranteed to be helpful) 2) Combining the booleans into a flag allows to combine read/writes from memory. 3) With the upcoming slot abstraction changes, it allows to have core and extended flags, in a memory efficient way. Author: Ashutosh Bapat and Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-10-16 00:24:33 +02:00
((slot) == NULL || TTS_EMPTY(slot))
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
/* in executor/execTuples.c */
Allow tupleslots to have a fixed tupledesc, use in executor nodes. The reason for doing so is that it will allow expression evaluation to optimize based on the underlying tupledesc. In particular it will allow to JIT tuple deforming together with the expression itself. For that expression initialization needs to be moved after the relevant slots are initialized - mostly unproblematic, except in the case of nodeWorktablescan.c. After doing so there's no need for ExecAssignResultType() and ExecAssignResultTypeFromTL() anymore, as all former callers have been converted to create a slot with a fixed descriptor. When creating a slot with a fixed descriptor, tts_values/isnull can be allocated together with the main slot, reducing allocation overhead and increasing cache density a bit. Author: Andres Freund Discussion: https://postgr.es/m/20171206093717.vqdxe5icqttpxs3p@alap3.anarazel.de
2018-02-17 06:17:38 +01:00
extern TupleTableSlot *MakeTupleTableSlot(TupleDesc desc);
extern TupleTableSlot *ExecAllocTableSlot(List **tupleTable, TupleDesc desc);
Replace the array-style TupleTable data structure with a simple List of TupleTableSlot nodes. This eliminates the need to count in advance how many Slots will be needed, which seems more than worth the small increase in the amount of palloc traffic during executor startup. The ExecCountSlots infrastructure is now all dead code, but I'll remove it in a separate commit for clarity. Per a comment from Robert Haas.
2009-09-27 22:09:58 +02:00
extern void ExecResetTupleTable(List *tupleTable, bool shouldFree);
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
extern TupleTableSlot *MakeSingleTupleTableSlot(TupleDesc tupdesc);
extern void ExecDropSingleTupleTableSlot(TupleTableSlot *slot);
Fix problems with cached tuple descriptors disappearing while still in use by creating a reference-count mechanism, similar to what we did a long time ago for catcache entries. The back branches have an ugly solution involving lots of extra copies, but this way is more efficient. Reference counting is only applied to tupdescs that are actually in caches --- there seems no need to use it for tupdescs that are generated in the executor, since they'll go away during plan shutdown by virtue of being in the per-query memory context. Neil Conway and Tom Lane
2006-06-16 20:42:24 +02:00
extern void ExecSetSlotDescriptor(TupleTableSlot *slot, TupleDesc tupdesc);
Split ExecStoreTuple into ExecStoreHeapTuple and ExecStoreBufferHeapTuple. Upcoming changes introduce further types of tuple table slots, in preparation of making table storage pluggable. New storage methods will have different representation of tuples, therefore the slot accessor should refer explicitly to heap tuples. Instead of just renaming the functions, split it into one function that accepts heap tuples not residing in buffers, and one accepting ones in buffers. Previously one function was used for both, but that was a bit awkward already, and splitting will allow us to represent slot types for tuples in buffers and normal memory separately. This is split out from the patch introducing abstract slots, as this largely consists out of mechanical changes. Author: Ashutosh Bapat Reviewed-By: Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-09-26 01:27:48 +02:00
extern TupleTableSlot *ExecStoreHeapTuple(HeapTuple tuple,
TupleTableSlot *slot,
bool shouldFree);
extern TupleTableSlot *ExecStoreBufferHeapTuple(HeapTuple tuple,
TupleTableSlot *slot,
Buffer buffer);
Create infrastructure for 'MinimalTuple' representation of in-memory tuples with less header overhead than a regular HeapTuple, per my recent proposal. Teach TupleTableSlot code how to deal with these. As proof of concept, change tuplestore.c to store MinimalTuples instead of HeapTuples. Future patches will expand the concept to other places where it is useful.
2006-06-27 04:51:40 +02:00
extern TupleTableSlot *ExecStoreMinimalTuple(MinimalTuple mtup,
pgindent run for 8.2.
2006-10-04 02:30:14 +02:00
TupleTableSlot *slot,
bool shouldFree);
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
extern TupleTableSlot *ExecClearTuple(TupleTableSlot *slot);
extern TupleTableSlot *ExecStoreVirtualTuple(TupleTableSlot *slot);
extern TupleTableSlot *ExecStoreAllNullTuple(TupleTableSlot *slot);
extern HeapTuple ExecCopySlotTuple(TupleTableSlot *slot);
Create infrastructure for 'MinimalTuple' representation of in-memory tuples with less header overhead than a regular HeapTuple, per my recent proposal. Teach TupleTableSlot code how to deal with these. As proof of concept, change tuplestore.c to store MinimalTuples instead of HeapTuples. Future patches will expand the concept to other places where it is useful.
2006-06-27 04:51:40 +02:00
extern MinimalTuple ExecCopySlotMinimalTuple(TupleTableSlot *slot);
Rejigger materializing and fetching a HeapTuple from a slot. Previously materializing a slot always returned a HeapTuple. As current work aims to reduce the reliance on HeapTuples (so other storage systems can work efficiently), that needs to change. Thus split the tasks of materializing a slot (i.e. making it independent from the underlying storage / other memory contexts) from fetching a HeapTuple from the slot. For brevity, allow to fetch a HeapTuple from a slot and materializing the slot at the same time, controlled by a parameter. For now some callers of ExecFetchSlotHeapTuple, with materialize = true, expect that changes to the heap tuple will be reflected in the underlying slot. Those places will be adapted in due course, so while not pretty, that's OK for now. Also rename ExecFetchSlotTuple to ExecFetchSlotHeapTupleDatum and ExecFetchSlotTupleDatum to ExecFetchSlotHeapTupleDatum, as it's likely that future storage methods will need similar methods. There already is ExecFetchSlotMinimalTuple, so the new names make the naming scheme more coherent. Author: Ashutosh Bapat and Andres Freund, with changes by Amit Khandekar Discussion: https://postgr.es/m/20181105210039.hh4vvi4vwoq5ba2q@alap3.anarazel.de
2018-11-15 23:26:14 +01:00
extern HeapTuple ExecFetchSlotHeapTuple(TupleTableSlot *slot, bool materialize, bool *shoulFree);
extern MinimalTuple ExecFetchSlotMinimalTuple(TupleTableSlot *slot,
bool *shouldFree);
extern Datum ExecFetchSlotHeapTupleDatum(TupleTableSlot *slot);
extern void ExecMaterializeSlot(TupleTableSlot *slot);
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
extern TupleTableSlot *ExecCopySlot(TupleTableSlot *dstslot,
Standard pgindent run for 8.1.
2005-10-15 04:49:52 +02:00
TupleTableSlot *srcslot);
Move generic slot support functions from heaptuple.c into execTuples.c. heaptuple.c was never a particular good fit for slot_getattr(), slot_getsomeattrs() and slot_getmissingattrs(), but in upcoming changes slots will be made more abstract (allowing slots that contain different types of tuples), making it clearly the wrong place. Note that slot_deform_tuple() remains in it's current place, as it clearly deals with a HeapTuple. getmissingattrs() also remains, but it's less clear that that's correct - but execTuples.c wouldn't be the right place. Author: Ashutosh Bapat. Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-10-15 00:18:16 +02:00
extern void slot_getmissingattrs(TupleTableSlot *slot, int startAttNum,
int lastAttNum);
extern Datum slot_getattr(TupleTableSlot *slot, int attnum,
bool *isnull);
extern void slot_getsomeattrs(TupleTableSlot *slot, int attnum);
Standard pgindent run for 8.1.
2005-10-15 04:49:52 +02:00
Avoid O(N^2) overhead in repeated nocachegetattr calls when columns of a tuple are being accessed via ExecEvalVar and the attcacheoff shortcut isn't usable (due to nulls and/or varlena columns). To do this, cache Datums extracted from a tuple in the associated TupleTableSlot. Also some code cleanup in and around the TupleTable handling. Atsushi Ogawa with some kibitzing by Tom Lane.
2005-03-14 05:41:13 +01:00
/* in access/common/heaptuple.c */
Revise TupleTableSlot code to avoid unnecessary construction and disassembly of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-16 22:38:10 +01:00
extern bool slot_attisnull(TupleTableSlot *slot, int attnum);
Fix WHERE CURRENT OF when the referenced cursor uses an index-only scan. "UPDATE/DELETE WHERE CURRENT OF cursor_name" failed, with an error message like "cannot extract system attribute from virtual tuple", if the cursor was using a index-only scan for the target table. Fix it by digging the current TID out of the indexscan state. It seems likely that the same failure could occur for CustomScan plans and perhaps some FDW plan types, so that leaving this to be treated as an internal error with an obscure message isn't as good an idea as it first seemed. Hence, add a bit of heaptuple.c infrastructure to let us deliver a more on-topic message. I chose to make the message match what you get for the case where execCurrentOf can't identify the target scan node at all, "cursor "foo" is not a simply updatable scan of table "bar"". Perhaps it should be different, but we can always adjust that later. In the future, it might be nice to provide hooks that would let custom scan providers and/or FDWs deal with this in other ways; but that's not a suitable topic for a back-patchable bug fix. It's been like this all along, so back-patch to all supported branches. Yugo Nagata and Tom Lane Discussion: https://postgr.es/m/20180201013349.937dfc5f.nagata@sraoss.co.jp
2018-03-17 19:59:31 +01:00
extern bool slot_getsysattr(TupleTableSlot *slot, int attnum,
Datum *value, bool *isnull);
Move generic slot support functions from heaptuple.c into execTuples.c. heaptuple.c was never a particular good fit for slot_getattr(), slot_getsomeattrs() and slot_getmissingattrs(), but in upcoming changes slots will be made more abstract (allowing slots that contain different types of tuples), making it clearly the wrong place. Note that slot_deform_tuple() remains in it's current place, as it clearly deals with a HeapTuple. getmissingattrs() also remains, but it's less clear that that's correct - but execTuples.c wouldn't be the right place. Author: Ashutosh Bapat. Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-10-15 00:18:16 +02:00
extern Datum getmissingattr(TupleDesc tupleDesc,
int attnum, bool *isnull);
Avoid O(N^2) overhead in repeated nocachegetattr calls when columns of a tuple are being accessed via ExecEvalVar and the attcacheoff shortcut isn't usable (due to nulls and/or varlena columns). To do this, cache Datums extracted from a tuple in the associated TupleTableSlot. Also some code cleanup in and around the TupleTable handling. Atsushi Ogawa with some kibitzing by Tom Lane.
2005-03-14 05:41:13 +01:00
Hide a static inline from FRONTEND code. For some reason pg_waldump is including tuptable.h, and the recent addition of a static inline function to it is causing problems on older buildfarm members that fail to optimize such functions away completely. I wonder if this situation doesn't mean that some header refactoring is called for ... but as a band-aid, wrap the static function in "#ifndef FRONTEND". Discussion: https://postgr.es/m/20180824154237.mabsv6fsz5q37bma@alap3.anarazel.de
2018-09-10 18:47:02 +02:00
#ifndef FRONTEND
Deduplicate code between slot_getallattrs() and slot_getsomeattrs(). Code in slot_getallattrs() is the same as if slot_getsomeattrs() is called with number of attributes specified in the tuple descriptor. Implement it that way instead of duplicating the code between those two functions. This is part of a patchseries abstracting TupleTableSlots so they can store arbitrary forms of tuples, but is a nice enough cleanup on its own. Author: Ashutosh Bapat Reviewed-By: Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-08-24 01:58:53 +02:00
/*
* slot_getallattrs
* This function forces all the entries of the slot's Datum/isnull
* arrays to be valid. The caller may then extract data directly
* from those arrays instead of using slot_getattr.
*/
static inline void
slot_getallattrs(TupleTableSlot *slot)
{
slot_getsomeattrs(slot, slot->tts_tupleDescriptor->natts);
}
Hide a static inline from FRONTEND code. For some reason pg_waldump is including tuptable.h, and the recent addition of a static inline function to it is causing problems on older buildfarm members that fail to optimize such functions away completely. I wonder if this situation doesn't mean that some header refactoring is called for ... but as a band-aid, wrap the static function in "#ifndef FRONTEND". Discussion: https://postgr.es/m/20180824154237.mabsv6fsz5q37bma@alap3.anarazel.de
2018-09-10 18:47:02 +02:00
#endif
Phase 2 of pgindent updates. Change pg_bsd_indent to follow upstream rules for placement of comments to the right of code, and remove pgindent hack that caused comments following #endif to not obey the general rule. Commit e3860ffa4dd0dad0dd9eea4be9cc1412373a8c89 wasn't actually using the published version of pg_bsd_indent, but a hacked-up version that tried to minimize the amount of movement of comments to the right of code. The situation of interest is where such a comment has to be moved to the right of its default placement at column 33 because there's code there. BSD indent has always moved right in units of tab stops in such cases --- but in the previous incarnation, indent was working in 8-space tab stops, while now it knows we use 4-space tabs. So the net result is that in about half the cases, such comments are placed one tab stop left of before. This is better all around: it leaves more room on the line for comment text, and it means that in such cases the comment uniformly starts at the next 4-space tab stop after the code, rather than sometimes one and sometimes two tabs after. Also, ensure that comments following #endif are indented the same as comments following other preprocessor commands such as #else. That inconsistency turns out to have been self-inflicted damage from a poorly-thought-through post-indent "fixup" in pgindent. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
2017-06-21 21:18:54 +02:00
#endif /* TUPTABLE_H */