1996-07-09 08:22:35 +02:00
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/*-------------------------------------------------------------------------
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*
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1999-02-14 00:22:53 +01:00
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* executor.h
|
1997-09-07 07:04:48 +02:00
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* support for the POSTGRES executor module
|
1996-07-09 08:22:35 +02:00
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*
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*
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2018-01-03 05:30:12 +01:00
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* Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group
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2000-01-26 06:58:53 +01:00
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* Portions Copyright (c) 1994, Regents of the University of California
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1996-07-09 08:22:35 +02:00
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*
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2010-09-20 22:08:53 +02:00
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* src/include/executor/executor.h
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1996-07-09 08:22:35 +02:00
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*
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*-------------------------------------------------------------------------
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*/
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#ifndef EXECUTOR_H
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#define EXECUTOR_H
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1999-07-16 01:04:24 +02:00
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#include "executor/execdesc.h"
|
2007-02-20 18:32:18 +01:00
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|
#include "nodes/parsenodes.h"
|
2018-01-29 21:16:53 +01:00
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#include "utils/memutils.h"
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1996-11-05 09:18:44 +01:00
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2002-12-05 16:50:39 +01:00
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2006-02-28 05:10:28 +01:00
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/*
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* The "eflags" argument to ExecutorStart and the various ExecInitNode
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* routines is a bitwise OR of the following flag bits, which tell the
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* called plan node what to expect. Note that the flags will get modified
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* as they are passed down the plan tree, since an upper node may require
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* functionality in its subnode not demanded of the plan as a whole
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* (example: MergeJoin requires mark/restore capability in its inner input),
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* or an upper node may shield its input from some functionality requirement
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* (example: Materialize shields its input from needing to do backward scan).
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*
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* EXPLAIN_ONLY indicates that the plan tree is being initialized just so
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* EXPLAIN can print it out; it will not be run. Hence, no side-effects
|
Restructure SELECT INTO's parsetree representation into CreateTableAsStmt.
Making this operation look like a utility statement seems generally a good
idea, and particularly so in light of the desire to provide command
triggers for utility statements. The original choice of representing it as
SELECT with an IntoClause appendage had metastasized into rather a lot of
places, unfortunately, so that this patch is a great deal more complicated
than one might at first expect.
In particular, keeping EXPLAIN working for SELECT INTO and CREATE TABLE AS
subcommands required restructuring some EXPLAIN-related APIs. Add-on code
that calls ExplainOnePlan or ExplainOneUtility, or uses
ExplainOneQuery_hook, will need adjustment.
Also, the cases PREPARE ... SELECT INTO and CREATE RULE ... SELECT INTO,
which formerly were accepted though undocumented, are no longer accepted.
The PREPARE case can be replaced with use of CREATE TABLE AS EXECUTE.
The CREATE RULE case doesn't seem to have much real-world use (since the
rule would work only once before failing with "table already exists"),
so we'll not bother with that one.
Both SELECT INTO and CREATE TABLE AS still return a command tag of
"SELECT nnnn". There was some discussion of returning "CREATE TABLE nnnn",
but for the moment backwards compatibility wins the day.
Andres Freund and Tom Lane
2012-03-20 02:37:19 +01:00
|
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* of startup should occur. However, error checks (such as permission checks)
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* should be performed.
|
2006-02-28 05:10:28 +01:00
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|
*
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* REWIND indicates that the plan node should try to efficiently support
|
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|
|
* rescans without parameter changes. (Nodes must support ExecReScan calls
|
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|
|
* in any case, but if this flag was not given, they are at liberty to do it
|
2014-05-06 18:12:18 +02:00
|
|
|
* through complete recalculation. Note that a parameter change forces a
|
2006-02-28 05:10:28 +01:00
|
|
|
* full recalculation in any case.)
|
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|
|
*
|
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|
|
* BACKWARD indicates that the plan node must respect the es_direction flag.
|
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|
|
* When this is not passed, the plan node will only be run forwards.
|
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|
|
*
|
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|
|
* MARK indicates that the plan node must support Mark/Restore calls.
|
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|
|
* When this is not passed, no Mark/Restore will occur.
|
2011-02-27 19:43:29 +01:00
|
|
|
*
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|
|
|
* SKIP_TRIGGERS tells ExecutorStart/ExecutorFinish to skip calling
|
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|
|
* AfterTriggerBeginQuery/AfterTriggerEndQuery. This does not necessarily
|
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|
|
* mean that the plan can't queue any AFTER triggers; just that the caller
|
|
|
|
* is responsible for there being a trigger context for them to be queued in.
|
Restructure SELECT INTO's parsetree representation into CreateTableAsStmt.
Making this operation look like a utility statement seems generally a good
idea, and particularly so in light of the desire to provide command
triggers for utility statements. The original choice of representing it as
SELECT with an IntoClause appendage had metastasized into rather a lot of
places, unfortunately, so that this patch is a great deal more complicated
than one might at first expect.
In particular, keeping EXPLAIN working for SELECT INTO and CREATE TABLE AS
subcommands required restructuring some EXPLAIN-related APIs. Add-on code
that calls ExplainOnePlan or ExplainOneUtility, or uses
ExplainOneQuery_hook, will need adjustment.
Also, the cases PREPARE ... SELECT INTO and CREATE RULE ... SELECT INTO,
which formerly were accepted though undocumented, are no longer accepted.
The PREPARE case can be replaced with use of CREATE TABLE AS EXECUTE.
The CREATE RULE case doesn't seem to have much real-world use (since the
rule would work only once before failing with "table already exists"),
so we'll not bother with that one.
Both SELECT INTO and CREATE TABLE AS still return a command tag of
"SELECT nnnn". There was some discussion of returning "CREATE TABLE nnnn",
but for the moment backwards compatibility wins the day.
Andres Freund and Tom Lane
2012-03-20 02:37:19 +01:00
|
|
|
*
|
|
|
|
* WITH/WITHOUT_OIDS tell the executor to emit tuples with or without space
|
2014-05-06 18:12:18 +02:00
|
|
|
* for OIDs, respectively. These are currently used only for CREATE TABLE AS.
|
Restructure SELECT INTO's parsetree representation into CreateTableAsStmt.
Making this operation look like a utility statement seems generally a good
idea, and particularly so in light of the desire to provide command
triggers for utility statements. The original choice of representing it as
SELECT with an IntoClause appendage had metastasized into rather a lot of
places, unfortunately, so that this patch is a great deal more complicated
than one might at first expect.
In particular, keeping EXPLAIN working for SELECT INTO and CREATE TABLE AS
subcommands required restructuring some EXPLAIN-related APIs. Add-on code
that calls ExplainOnePlan or ExplainOneUtility, or uses
ExplainOneQuery_hook, will need adjustment.
Also, the cases PREPARE ... SELECT INTO and CREATE RULE ... SELECT INTO,
which formerly were accepted though undocumented, are no longer accepted.
The PREPARE case can be replaced with use of CREATE TABLE AS EXECUTE.
The CREATE RULE case doesn't seem to have much real-world use (since the
rule would work only once before failing with "table already exists"),
so we'll not bother with that one.
Both SELECT INTO and CREATE TABLE AS still return a command tag of
"SELECT nnnn". There was some discussion of returning "CREATE TABLE nnnn",
but for the moment backwards compatibility wins the day.
Andres Freund and Tom Lane
2012-03-20 02:37:19 +01:00
|
|
|
* If neither is set, the plan may or may not produce tuples including OIDs.
|
2006-02-28 05:10:28 +01:00
|
|
|
*/
|
2006-10-04 02:30:14 +02:00
|
|
|
#define EXEC_FLAG_EXPLAIN_ONLY 0x0001 /* EXPLAIN, no ANALYZE */
|
|
|
|
#define EXEC_FLAG_REWIND 0x0002 /* need efficient rescan */
|
|
|
|
#define EXEC_FLAG_BACKWARD 0x0004 /* need backward scan */
|
|
|
|
#define EXEC_FLAG_MARK 0x0008 /* need mark/restore */
|
2011-04-10 17:42:00 +02:00
|
|
|
#define EXEC_FLAG_SKIP_TRIGGERS 0x0010 /* skip AfterTrigger calls */
|
Restructure SELECT INTO's parsetree representation into CreateTableAsStmt.
Making this operation look like a utility statement seems generally a good
idea, and particularly so in light of the desire to provide command
triggers for utility statements. The original choice of representing it as
SELECT with an IntoClause appendage had metastasized into rather a lot of
places, unfortunately, so that this patch is a great deal more complicated
than one might at first expect.
In particular, keeping EXPLAIN working for SELECT INTO and CREATE TABLE AS
subcommands required restructuring some EXPLAIN-related APIs. Add-on code
that calls ExplainOnePlan or ExplainOneUtility, or uses
ExplainOneQuery_hook, will need adjustment.
Also, the cases PREPARE ... SELECT INTO and CREATE RULE ... SELECT INTO,
which formerly were accepted though undocumented, are no longer accepted.
The PREPARE case can be replaced with use of CREATE TABLE AS EXECUTE.
The CREATE RULE case doesn't seem to have much real-world use (since the
rule would work only once before failing with "table already exists"),
so we'll not bother with that one.
Both SELECT INTO and CREATE TABLE AS still return a command tag of
"SELECT nnnn". There was some discussion of returning "CREATE TABLE nnnn",
but for the moment backwards compatibility wins the day.
Andres Freund and Tom Lane
2012-03-20 02:37:19 +01:00
|
|
|
#define EXEC_FLAG_WITH_OIDS 0x0020 /* force OIDs in returned tuples */
|
|
|
|
#define EXEC_FLAG_WITHOUT_OIDS 0x0040 /* force no OIDs in returned tuples */
|
2013-03-04 01:23:31 +01:00
|
|
|
#define EXEC_FLAG_WITH_NO_DATA 0x0080 /* rel scannability doesn't matter */
|
2006-02-28 05:10:28 +01:00
|
|
|
|
|
|
|
|
2008-11-19 02:10:24 +01:00
|
|
|
/* Hook for plugins to get control in ExecutorStart() */
|
|
|
|
typedef void (*ExecutorStart_hook_type) (QueryDesc *queryDesc, int eflags);
|
|
|
|
extern PGDLLIMPORT ExecutorStart_hook_type ExecutorStart_hook;
|
|
|
|
|
2008-07-18 20:23:47 +02:00
|
|
|
/* Hook for plugins to get control in ExecutorRun() */
|
2008-10-31 22:07:55 +01:00
|
|
|
typedef void (*ExecutorRun_hook_type) (QueryDesc *queryDesc,
|
2017-06-21 20:39:04 +02:00
|
|
|
ScanDirection direction,
|
|
|
|
uint64 count,
|
|
|
|
bool execute_once);
|
2008-07-18 20:23:47 +02:00
|
|
|
extern PGDLLIMPORT ExecutorRun_hook_type ExecutorRun_hook;
|
|
|
|
|
2011-02-27 19:43:29 +01:00
|
|
|
/* Hook for plugins to get control in ExecutorFinish() */
|
|
|
|
typedef void (*ExecutorFinish_hook_type) (QueryDesc *queryDesc);
|
|
|
|
extern PGDLLIMPORT ExecutorFinish_hook_type ExecutorFinish_hook;
|
|
|
|
|
2008-11-19 02:10:24 +01:00
|
|
|
/* Hook for plugins to get control in ExecutorEnd() */
|
|
|
|
typedef void (*ExecutorEnd_hook_type) (QueryDesc *queryDesc);
|
|
|
|
extern PGDLLIMPORT ExecutorEnd_hook_type ExecutorEnd_hook;
|
|
|
|
|
2010-07-09 16:06:01 +02:00
|
|
|
/* Hook for plugins to get control in ExecCheckRTPerms() */
|
2010-07-22 02:47:59 +02:00
|
|
|
typedef bool (*ExecutorCheckPerms_hook_type) (List *, bool);
|
2010-07-09 16:06:01 +02:00
|
|
|
extern PGDLLIMPORT ExecutorCheckPerms_hook_type ExecutorCheckPerms_hook;
|
|
|
|
|
2008-07-18 20:23:47 +02:00
|
|
|
|
1996-07-09 08:22:35 +02:00
|
|
|
/*
|
|
|
|
* prototypes from functions in execAmi.c
|
|
|
|
*/
|
2014-11-21 00:36:07 +01:00
|
|
|
struct Path; /* avoid including relation.h here */
|
|
|
|
|
2010-07-12 19:01:06 +02:00
|
|
|
extern void ExecReScan(PlanState *node);
|
2003-08-08 23:42:59 +02:00
|
|
|
extern void ExecMarkPos(PlanState *node);
|
|
|
|
extern void ExecRestrPos(PlanState *node);
|
2014-11-21 00:36:07 +01:00
|
|
|
extern bool ExecSupportsMarkRestore(struct Path *pathnode);
|
2003-03-10 04:53:52 +01:00
|
|
|
extern bool ExecSupportsBackwardScan(Plan *node);
|
2009-09-13 00:12:09 +02:00
|
|
|
extern bool ExecMaterializesOutput(NodeTag plantype);
|
1996-07-09 08:22:35 +02:00
|
|
|
|
2007-06-11 03:16:30 +02:00
|
|
|
/*
|
|
|
|
* prototypes from functions in execCurrent.c
|
|
|
|
*/
|
2007-11-15 23:25:18 +01:00
|
|
|
extern bool execCurrentOf(CurrentOfExpr *cexpr,
|
2007-11-15 22:14:46 +01:00
|
|
|
ExprContext *econtext,
|
|
|
|
Oid table_oid,
|
|
|
|
ItemPointer current_tid);
|
2007-06-11 03:16:30 +02:00
|
|
|
|
2003-01-11 00:54:24 +01:00
|
|
|
/*
|
|
|
|
* prototypes from functions in execGrouping.c
|
|
|
|
*/
|
2018-02-16 06:55:31 +01:00
|
|
|
extern ExprState *execTuplesMatchPrepare(TupleDesc desc,
|
|
|
|
int numCols,
|
|
|
|
AttrNumber *keyColIdx,
|
|
|
|
Oid *eqOperators,
|
|
|
|
PlanState *parent);
|
2007-01-10 19:06:05 +01:00
|
|
|
extern void execTuplesHashPrepare(int numCols,
|
|
|
|
Oid *eqOperators,
|
2018-02-16 06:55:31 +01:00
|
|
|
Oid **eqFuncOids,
|
2007-01-10 19:06:05 +01:00
|
|
|
FmgrInfo **hashFunctions);
|
2018-02-16 06:55:31 +01:00
|
|
|
extern TupleHashTable BuildTupleHashTable(PlanState *parent,
|
|
|
|
TupleDesc inputDesc,
|
|
|
|
int numCols, AttrNumber *keyColIdx,
|
|
|
|
Oid *eqfuncoids,
|
2003-08-04 02:43:34 +02:00
|
|
|
FmgrInfo *hashfunctions,
|
2016-10-15 02:22:51 +02:00
|
|
|
long nbuckets, Size additionalsize,
|
2003-08-04 02:43:34 +02:00
|
|
|
MemoryContext tablecxt,
|
2016-12-16 16:03:08 +01:00
|
|
|
MemoryContext tempcxt, bool use_variable_hash_iv);
|
2003-01-11 00:54:24 +01:00
|
|
|
extern TupleHashEntry LookupTupleHashEntry(TupleHashTable hashtable,
|
2003-08-04 02:43:34 +02:00
|
|
|
TupleTableSlot *slot,
|
|
|
|
bool *isnew);
|
2007-02-06 03:59:15 +01:00
|
|
|
extern TupleHashEntry FindTupleHashEntry(TupleHashTable hashtable,
|
2007-11-15 22:14:46 +01:00
|
|
|
TupleTableSlot *slot,
|
2018-02-16 06:55:31 +01:00
|
|
|
ExprState *eqcomp,
|
2007-11-15 22:14:46 +01:00
|
|
|
FmgrInfo *hashfunctions);
|
2003-01-11 00:54:24 +01:00
|
|
|
|
1996-07-09 08:22:35 +02:00
|
|
|
/*
|
|
|
|
* prototypes from functions in execJunk.c
|
|
|
|
*/
|
2004-10-07 20:38:51 +02:00
|
|
|
extern JunkFilter *ExecInitJunkFilter(List *targetList, bool hasoid,
|
2001-10-25 07:50:21 +02:00
|
|
|
TupleTableSlot *slot);
|
2004-10-07 20:38:51 +02:00
|
|
|
extern JunkFilter *ExecInitJunkFilterConversion(List *targetList,
|
2005-10-15 04:49:52 +02:00
|
|
|
TupleDesc cleanTupType,
|
|
|
|
TupleTableSlot *slot);
|
2006-12-04 03:06:55 +01:00
|
|
|
extern AttrNumber ExecFindJunkAttribute(JunkFilter *junkfilter,
|
2007-11-15 22:14:46 +01:00
|
|
|
const char *attrName);
|
2011-01-13 02:47:02 +01:00
|
|
|
extern AttrNumber ExecFindJunkAttributeInTlist(List *targetlist,
|
2011-04-10 17:42:00 +02:00
|
|
|
const char *attrName);
|
2006-12-04 03:06:55 +01:00
|
|
|
extern Datum ExecGetJunkAttribute(TupleTableSlot *slot, AttrNumber attno,
|
2007-11-15 22:14:46 +01:00
|
|
|
bool *isNull);
|
2005-03-16 22:38:10 +01:00
|
|
|
extern TupleTableSlot *ExecFilterJunk(JunkFilter *junkfilter,
|
2005-10-15 04:49:52 +02:00
|
|
|
TupleTableSlot *slot);
|
1996-07-09 08:22:35 +02:00
|
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
* prototypes from functions in execMain.c
|
|
|
|
*/
|
2006-02-28 05:10:28 +01:00
|
|
|
extern void ExecutorStart(QueryDesc *queryDesc, int eflags);
|
2008-11-19 02:10:24 +01:00
|
|
|
extern void standard_ExecutorStart(QueryDesc *queryDesc, int eflags);
|
2008-10-31 22:07:55 +01:00
|
|
|
extern void ExecutorRun(QueryDesc *queryDesc,
|
2017-03-23 18:05:48 +01:00
|
|
|
ScanDirection direction, uint64 count, bool execute_once);
|
2008-10-31 22:07:55 +01:00
|
|
|
extern void standard_ExecutorRun(QueryDesc *queryDesc,
|
Phase 3 of pgindent updates.
Don't move parenthesized lines to the left, even if that means they
flow past the right margin.
By default, BSD indent lines up statement continuation lines that are
within parentheses so that they start just to the right of the preceding
left parenthesis. However, traditionally, if that resulted in the
continuation line extending to the right of the desired right margin,
then indent would push it left just far enough to not overrun the margin,
if it could do so without making the continuation line start to the left of
the current statement indent. That makes for a weird mix of indentations
unless one has been completely rigid about never violating the 80-column
limit.
This behavior has been pretty universally panned by Postgres developers.
Hence, disable it with indent's new -lpl switch, so that parenthesized
lines are always lined up with the preceding left paren.
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 21:35:54 +02:00
|
|
|
ScanDirection direction, uint64 count, bool execute_once);
|
2011-02-27 19:43:29 +01:00
|
|
|
extern void ExecutorFinish(QueryDesc *queryDesc);
|
|
|
|
extern void standard_ExecutorFinish(QueryDesc *queryDesc);
|
2002-12-05 16:50:39 +01:00
|
|
|
extern void ExecutorEnd(QueryDesc *queryDesc);
|
2008-11-19 02:10:24 +01:00
|
|
|
extern void standard_ExecutorEnd(QueryDesc *queryDesc);
|
2003-03-11 20:40:24 +01:00
|
|
|
extern void ExecutorRewind(QueryDesc *queryDesc);
|
2010-07-22 02:47:59 +02:00
|
|
|
extern bool ExecCheckRTPerms(List *rangeTable, bool ereport_on_violation);
|
2017-09-07 16:55:45 +02:00
|
|
|
extern void CheckValidResultRel(ResultRelInfo *resultRelInfo, CmdType operation);
|
2008-03-28 01:21:56 +01:00
|
|
|
extern void InitResultRelInfo(ResultRelInfo *resultRelInfo,
|
|
|
|
Relation resultRelationDesc,
|
|
|
|
Index resultRelationIndex,
|
2017-01-04 20:36:34 +01:00
|
|
|
Relation partition_root,
|
2009-12-15 05:57:48 +01:00
|
|
|
int instrument_options);
|
2007-08-15 23:39:50 +02:00
|
|
|
extern ResultRelInfo *ExecGetTriggerResultRel(EState *estate, Oid relid);
|
2017-05-16 18:46:32 +02:00
|
|
|
extern void ExecCleanUpTriggerState(EState *estate);
|
2004-01-22 03:23:21 +01:00
|
|
|
extern bool ExecContextForcesOids(PlanState *planstate, bool *hasoids);
|
2003-07-21 19:05:12 +02:00
|
|
|
extern void ExecConstraints(ResultRelInfo *resultRelInfo,
|
2018-06-11 22:53:33 +02:00
|
|
|
TupleTableSlot *slot, EState *estate);
|
2018-01-05 21:18:03 +01:00
|
|
|
extern bool ExecPartitionCheck(ResultRelInfo *resultRelInfo,
|
2018-06-11 22:53:33 +02:00
|
|
|
TupleTableSlot *slot, EState *estate, bool emitError);
|
2018-01-05 21:18:03 +01:00
|
|
|
extern void ExecPartitionCheckEmitError(ResultRelInfo *resultRelInfo,
|
2018-01-09 22:25:38 +01:00
|
|
|
TupleTableSlot *slot, EState *estate);
|
2015-04-25 02:34:26 +02:00
|
|
|
extern void ExecWithCheckOptions(WCOKind kind, ResultRelInfo *resultRelInfo,
|
2013-07-18 23:10:16 +02:00
|
|
|
TupleTableSlot *slot, EState *estate);
|
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE.
The newly added ON CONFLICT clause allows to specify an alternative to
raising a unique or exclusion constraint violation error when inserting.
ON CONFLICT refers to constraints that can either be specified using a
inference clause (by specifying the columns of a unique constraint) or
by naming a unique or exclusion constraint. DO NOTHING avoids the
constraint violation, without touching the pre-existing row. DO UPDATE
SET ... [WHERE ...] updates the pre-existing tuple, and has access to
both the tuple proposed for insertion and the existing tuple; the
optional WHERE clause can be used to prevent an update from being
executed. The UPDATE SET and WHERE clauses have access to the tuple
proposed for insertion using the "magic" EXCLUDED alias, and to the
pre-existing tuple using the table name or its alias.
This feature is often referred to as upsert.
This is implemented using a new infrastructure called "speculative
insertion". It is an optimistic variant of regular insertion that first
does a pre-check for existing tuples and then attempts an insert. If a
violating tuple was inserted concurrently, the speculatively inserted
tuple is deleted and a new attempt is made. If the pre-check finds a
matching tuple the alternative DO NOTHING or DO UPDATE action is taken.
If the insertion succeeds without detecting a conflict, the tuple is
deemed inserted.
To handle the possible ambiguity between the excluded alias and a table
named excluded, and for convenience with long relation names, INSERT
INTO now can alias its target table.
Bumps catversion as stored rules change.
Author: Peter Geoghegan, with significant contributions from Heikki
Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes.
Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs,
Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
|
|
|
extern LockTupleMode ExecUpdateLockMode(EState *estate, ResultRelInfo *relinfo);
|
Add support for doing late row locking in FDWs.
Previously, FDWs could only do "early row locking", that is lock a row as
soon as it's fetched, even though local restriction/join conditions might
discard the row later. This patch adds callbacks that allow FDWs to do
late locking in the same way that it's done for regular tables.
To make use of this feature, an FDW must support the "ctid" column as a
unique row identifier. Currently, since ctid has to be of type TID,
the feature is of limited use, though in principle it could be used by
postgres_fdw. We may eventually allow FDWs to specify another data type
for ctid, which would make it possible for more FDWs to use this feature.
This commit does not modify postgres_fdw to use late locking. We've
tested some prototype code for that, but it's not in committable shape,
and besides it's quite unclear whether it actually makes sense to do late
locking against a remote server. The extra round trips required are likely
to outweigh any benefit from improved concurrency.
Etsuro Fujita, reviewed by Ashutosh Bapat, and hacked up a lot by me
2015-05-12 20:10:10 +02:00
|
|
|
extern ExecRowMark *ExecFindRowMark(EState *estate, Index rti, bool missing_ok);
|
2011-01-13 02:47:02 +01:00
|
|
|
extern ExecAuxRowMark *ExecBuildAuxRowMark(ExecRowMark *erm, List *targetlist);
|
Re-implement EvalPlanQual processing to improve its performance and eliminate
a lot of strange behaviors that occurred in join cases. We now identify the
"current" row for every joined relation in UPDATE, DELETE, and SELECT FOR
UPDATE/SHARE queries. If an EvalPlanQual recheck is necessary, we jam the
appropriate row into each scan node in the rechecking plan, forcing it to emit
only that one row. The former behavior could rescan the whole of each joined
relation for each recheck, which was terrible for performance, and what's much
worse could result in duplicated output tuples.
Also, the original implementation of EvalPlanQual could not re-use the recheck
execution tree --- it had to go through a full executor init and shutdown for
every row to be tested. To avoid this overhead, I've associated a special
runtime Param with each LockRows or ModifyTable plan node, and arranged to
make every scan node below such a node depend on that Param. Thus, by
signaling a change in that Param, the EPQ machinery can just rescan the
already-built test plan.
This patch also adds a prohibition on set-returning functions in the
targetlist of SELECT FOR UPDATE/SHARE. This is needed to avoid the
duplicate-output-tuple problem. It seems fairly reasonable since the
other restrictions on SELECT FOR UPDATE are meant to ensure that there
is a unique correspondence between source tuples and result tuples,
which an output SRF destroys as much as anything else does.
2009-10-26 03:26:45 +01:00
|
|
|
extern TupleTableSlot *EvalPlanQual(EState *estate, EPQState *epqstate,
|
Improve concurrency of foreign key locking
This patch introduces two additional lock modes for tuples: "SELECT FOR
KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each
other, in contrast with already existing "SELECT FOR SHARE" and "SELECT
FOR UPDATE". UPDATE commands that do not modify the values stored in
the columns that are part of the key of the tuple now grab a SELECT FOR
NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently
with tuple locks of the FOR KEY SHARE variety.
Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this
means the concurrency improvement applies to them, which is the whole
point of this patch.
The added tuple lock semantics require some rejiggering of the multixact
module, so that the locking level that each transaction is holding can
be stored alongside its Xid. Also, multixacts now need to persist
across server restarts and crashes, because they can now represent not
only tuple locks, but also tuple updates. This means we need more
careful tracking of lifetime of pg_multixact SLRU files; since they now
persist longer, we require more infrastructure to figure out when they
can be removed. pg_upgrade also needs to be careful to copy
pg_multixact files over from the old server to the new, or at least part
of multixact.c state, depending on the versions of the old and new
servers.
Tuple time qualification rules (HeapTupleSatisfies routines) need to be
careful not to consider tuples with the "is multi" infomask bit set as
being only locked; they might need to look up MultiXact values (i.e.
possibly do pg_multixact I/O) to find out the Xid that updated a tuple,
whereas they previously were assured to only use information readily
available from the tuple header. This is considered acceptable, because
the extra I/O would involve cases that would previously cause some
commands to block waiting for concurrent transactions to finish.
Another important change is the fact that locking tuples that have
previously been updated causes the future versions to be marked as
locked, too; this is essential for correctness of foreign key checks.
This causes additional WAL-logging, also (there was previously a single
WAL record for a locked tuple; now there are as many as updated copies
of the tuple there exist.)
With all this in place, contention related to tuples being checked by
foreign key rules should be much reduced.
As a bonus, the old behavior that a subtransaction grabbing a stronger
tuple lock than the parent (sub)transaction held on a given tuple and
later aborting caused the weaker lock to be lost, has been fixed.
Many new spec files were added for isolation tester framework, to ensure
overall behavior is sane. There's probably room for several more tests.
There were several reviewers of this patch; in particular, Noah Misch
and Andres Freund spent considerable time in it. Original idea for the
patch came from Simon Riggs, after a problem report by Joel Jacobson.
Most code is from me, with contributions from Marti Raudsepp, Alexander
Shulgin, Noah Misch and Andres Freund.
This patch was discussed in several pgsql-hackers threads; the most
important start at the following message-ids:
AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com
1290721684-sup-3951@alvh.no-ip.org
1294953201-sup-2099@alvh.no-ip.org
1320343602-sup-2290@alvh.no-ip.org
1339690386-sup-8927@alvh.no-ip.org
4FE5FF020200002500048A3D@gw.wicourts.gov
4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
|
|
|
Relation relation, Index rti, int lockmode,
|
2007-11-30 22:22:54 +01:00
|
|
|
ItemPointer tid, TransactionId priorXmax);
|
Re-implement EvalPlanQual processing to improve its performance and eliminate
a lot of strange behaviors that occurred in join cases. We now identify the
"current" row for every joined relation in UPDATE, DELETE, and SELECT FOR
UPDATE/SHARE queries. If an EvalPlanQual recheck is necessary, we jam the
appropriate row into each scan node in the rechecking plan, forcing it to emit
only that one row. The former behavior could rescan the whole of each joined
relation for each recheck, which was terrible for performance, and what's much
worse could result in duplicated output tuples.
Also, the original implementation of EvalPlanQual could not re-use the recheck
execution tree --- it had to go through a full executor init and shutdown for
every row to be tested. To avoid this overhead, I've associated a special
runtime Param with each LockRows or ModifyTable plan node, and arranged to
make every scan node below such a node depend on that Param. Thus, by
signaling a change in that Param, the EPQ machinery can just rescan the
already-built test plan.
This patch also adds a prohibition on set-returning functions in the
targetlist of SELECT FOR UPDATE/SHARE. This is needed to avoid the
duplicate-output-tuple problem. It seems fairly reasonable since the
other restrictions on SELECT FOR UPDATE are meant to ensure that there
is a unique correspondence between source tuples and result tuples,
which an output SRF destroys as much as anything else does.
2009-10-26 03:26:45 +01:00
|
|
|
extern HeapTuple EvalPlanQualFetch(EState *estate, Relation relation,
|
2014-10-07 22:23:34 +02:00
|
|
|
int lockmode, LockWaitPolicy wait_policy, ItemPointer tid,
|
|
|
|
TransactionId priorXmax);
|
Re-implement EvalPlanQual processing to improve its performance and eliminate
a lot of strange behaviors that occurred in join cases. We now identify the
"current" row for every joined relation in UPDATE, DELETE, and SELECT FOR
UPDATE/SHARE queries. If an EvalPlanQual recheck is necessary, we jam the
appropriate row into each scan node in the rechecking plan, forcing it to emit
only that one row. The former behavior could rescan the whole of each joined
relation for each recheck, which was terrible for performance, and what's much
worse could result in duplicated output tuples.
Also, the original implementation of EvalPlanQual could not re-use the recheck
execution tree --- it had to go through a full executor init and shutdown for
every row to be tested. To avoid this overhead, I've associated a special
runtime Param with each LockRows or ModifyTable plan node, and arranged to
make every scan node below such a node depend on that Param. Thus, by
signaling a change in that Param, the EPQ machinery can just rescan the
already-built test plan.
This patch also adds a prohibition on set-returning functions in the
targetlist of SELECT FOR UPDATE/SHARE. This is needed to avoid the
duplicate-output-tuple problem. It seems fairly reasonable since the
other restrictions on SELECT FOR UPDATE are meant to ensure that there
is a unique correspondence between source tuples and result tuples,
which an output SRF destroys as much as anything else does.
2009-10-26 03:26:45 +01:00
|
|
|
extern void EvalPlanQualInit(EPQState *epqstate, EState *estate,
|
2011-01-13 02:47:02 +01:00
|
|
|
Plan *subplan, List *auxrowmarks, int epqParam);
|
|
|
|
extern void EvalPlanQualSetPlan(EPQState *epqstate,
|
2011-04-10 17:42:00 +02:00
|
|
|
Plan *subplan, List *auxrowmarks);
|
Re-implement EvalPlanQual processing to improve its performance and eliminate
a lot of strange behaviors that occurred in join cases. We now identify the
"current" row for every joined relation in UPDATE, DELETE, and SELECT FOR
UPDATE/SHARE queries. If an EvalPlanQual recheck is necessary, we jam the
appropriate row into each scan node in the rechecking plan, forcing it to emit
only that one row. The former behavior could rescan the whole of each joined
relation for each recheck, which was terrible for performance, and what's much
worse could result in duplicated output tuples.
Also, the original implementation of EvalPlanQual could not re-use the recheck
execution tree --- it had to go through a full executor init and shutdown for
every row to be tested. To avoid this overhead, I've associated a special
runtime Param with each LockRows or ModifyTable plan node, and arranged to
make every scan node below such a node depend on that Param. Thus, by
signaling a change in that Param, the EPQ machinery can just rescan the
already-built test plan.
This patch also adds a prohibition on set-returning functions in the
targetlist of SELECT FOR UPDATE/SHARE. This is needed to avoid the
duplicate-output-tuple problem. It seems fairly reasonable since the
other restrictions on SELECT FOR UPDATE are meant to ensure that there
is a unique correspondence between source tuples and result tuples,
which an output SRF destroys as much as anything else does.
2009-10-26 03:26:45 +01:00
|
|
|
extern void EvalPlanQualSetTuple(EPQState *epqstate, Index rti,
|
2010-02-26 03:01:40 +01:00
|
|
|
HeapTuple tuple);
|
Re-implement EvalPlanQual processing to improve its performance and eliminate
a lot of strange behaviors that occurred in join cases. We now identify the
"current" row for every joined relation in UPDATE, DELETE, and SELECT FOR
UPDATE/SHARE queries. If an EvalPlanQual recheck is necessary, we jam the
appropriate row into each scan node in the rechecking plan, forcing it to emit
only that one row. The former behavior could rescan the whole of each joined
relation for each recheck, which was terrible for performance, and what's much
worse could result in duplicated output tuples.
Also, the original implementation of EvalPlanQual could not re-use the recheck
execution tree --- it had to go through a full executor init and shutdown for
every row to be tested. To avoid this overhead, I've associated a special
runtime Param with each LockRows or ModifyTable plan node, and arranged to
make every scan node below such a node depend on that Param. Thus, by
signaling a change in that Param, the EPQ machinery can just rescan the
already-built test plan.
This patch also adds a prohibition on set-returning functions in the
targetlist of SELECT FOR UPDATE/SHARE. This is needed to avoid the
duplicate-output-tuple problem. It seems fairly reasonable since the
other restrictions on SELECT FOR UPDATE are meant to ensure that there
is a unique correspondence between source tuples and result tuples,
which an output SRF destroys as much as anything else does.
2009-10-26 03:26:45 +01:00
|
|
|
extern HeapTuple EvalPlanQualGetTuple(EPQState *epqstate, Index rti);
|
2010-02-26 03:01:40 +01:00
|
|
|
|
Re-implement EvalPlanQual processing to improve its performance and eliminate
a lot of strange behaviors that occurred in join cases. We now identify the
"current" row for every joined relation in UPDATE, DELETE, and SELECT FOR
UPDATE/SHARE queries. If an EvalPlanQual recheck is necessary, we jam the
appropriate row into each scan node in the rechecking plan, forcing it to emit
only that one row. The former behavior could rescan the whole of each joined
relation for each recheck, which was terrible for performance, and what's much
worse could result in duplicated output tuples.
Also, the original implementation of EvalPlanQual could not re-use the recheck
execution tree --- it had to go through a full executor init and shutdown for
every row to be tested. To avoid this overhead, I've associated a special
runtime Param with each LockRows or ModifyTable plan node, and arranged to
make every scan node below such a node depend on that Param. Thus, by
signaling a change in that Param, the EPQ machinery can just rescan the
already-built test plan.
This patch also adds a prohibition on set-returning functions in the
targetlist of SELECT FOR UPDATE/SHARE. This is needed to avoid the
duplicate-output-tuple problem. It seems fairly reasonable since the
other restrictions on SELECT FOR UPDATE are meant to ensure that there
is a unique correspondence between source tuples and result tuples,
which an output SRF destroys as much as anything else does.
2009-10-26 03:26:45 +01:00
|
|
|
#define EvalPlanQualSetSlot(epqstate, slot) ((epqstate)->origslot = (slot))
|
|
|
|
extern void EvalPlanQualFetchRowMarks(EPQState *epqstate);
|
|
|
|
extern TupleTableSlot *EvalPlanQualNext(EPQState *epqstate);
|
|
|
|
extern void EvalPlanQualBegin(EPQState *epqstate, EState *parentestate);
|
|
|
|
extern void EvalPlanQualEnd(EPQState *epqstate);
|
1999-05-25 18:15:34 +02:00
|
|
|
|
1996-07-09 08:22:35 +02:00
|
|
|
/*
|
2017-07-17 09:33:49 +02:00
|
|
|
* functions in execProcnode.c
|
1996-07-09 08:22:35 +02:00
|
|
|
*/
|
2006-02-28 05:10:28 +01:00
|
|
|
extern PlanState *ExecInitNode(Plan *node, EState *estate, int eflags);
|
2017-12-14 00:47:01 +01:00
|
|
|
extern void ExecSetExecProcNode(PlanState *node, ExecProcNodeMtd function);
|
2005-04-16 22:07:35 +02:00
|
|
|
extern Node *MultiExecProcNode(PlanState *node);
|
2003-08-08 23:42:59 +02:00
|
|
|
extern void ExecEndNode(PlanState *node);
|
Add a Gather executor node.
A Gather executor node runs any number of copies of a plan in an equal
number of workers and merges all of the results into a single tuple
stream. It can also run the plan itself, if the workers are
unavailable or haven't started up yet. It is intended to work with
the Partial Seq Scan node which will be added in future commits.
It could also be used to implement parallel query of a different sort
by itself, without help from Partial Seq Scan, if the single_copy mode
is used. In that mode, a worker executes the plan, and the parallel
leader does not, merely collecting the worker's results. So, a Gather
node could be inserted into a plan to split the execution of that plan
across two processes. Nested Gather nodes aren't currently supported,
but we might want to add support for that in the future.
There's nothing in the planner to actually generate Gather nodes yet,
so it's not quite time to break out the champagne. But we're getting
close.
Amit Kapila. Some designs suggestions were provided by me, and I also
reviewed the patch. Single-copy mode, documentation, and other minor
changes also by me.
2015-10-01 01:23:36 +02:00
|
|
|
extern bool ExecShutdownNode(PlanState *node);
|
2017-08-29 19:12:23 +02:00
|
|
|
extern void ExecSetTupleBound(int64 tuples_needed, PlanState *child_node);
|
1996-07-09 08:22:35 +02:00
|
|
|
|
2017-07-17 09:33:49 +02:00
|
|
|
|
|
|
|
/* ----------------------------------------------------------------
|
|
|
|
* ExecProcNode
|
|
|
|
*
|
|
|
|
* Execute the given node to return a(nother) tuple.
|
|
|
|
* ----------------------------------------------------------------
|
|
|
|
*/
|
|
|
|
#ifndef FRONTEND
|
|
|
|
static inline TupleTableSlot *
|
|
|
|
ExecProcNode(PlanState *node)
|
|
|
|
{
|
|
|
|
if (node->chgParam != NULL) /* something changed? */
|
|
|
|
ExecReScan(node); /* let ReScan handle this */
|
|
|
|
|
|
|
|
return node->ExecProcNode(node);
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
1996-07-09 08:22:35 +02:00
|
|
|
/*
|
Faster expression evaluation and targetlist projection.
This replaces the old, recursive tree-walk based evaluation, with
non-recursive, opcode dispatch based, expression evaluation.
Projection is now implemented as part of expression evaluation.
This both leads to significant performance improvements, and makes
future just-in-time compilation of expressions easier.
The speed gains primarily come from:
- non-recursive implementation reduces stack usage / overhead
- simple sub-expressions are implemented with a single jump, without
function calls
- sharing some state between different sub-expressions
- reduced amount of indirect/hard to predict memory accesses by laying
out operation metadata sequentially; including the avoidance of
nearly all of the previously used linked lists
- more code has been moved to expression initialization, avoiding
constant re-checks at evaluation time
Future just-in-time compilation (JIT) has become easier, as
demonstrated by released patches intended to be merged in a later
release, for primarily two reasons: Firstly, due to a stricter split
between expression initialization and evaluation, less code has to be
handled by the JIT. Secondly, due to the non-recursive nature of the
generated "instructions", less performance-critical code-paths can
easily be shared between interpreted and compiled evaluation.
The new framework allows for significant future optimizations. E.g.:
- basic infrastructure for to later reduce the per executor-startup
overhead of expression evaluation, by caching state in prepared
statements. That'd be helpful in OLTPish scenarios where
initialization overhead is measurable.
- optimizing the generated "code". A number of proposals for potential
work has already been made.
- optimizing the interpreter. Similarly a number of proposals have
been made here too.
The move of logic into the expression initialization step leads to some
backward-incompatible changes:
- Function permission checks are now done during expression
initialization, whereas previously they were done during
execution. In edge cases this can lead to errors being raised that
previously wouldn't have been, e.g. a NULL array being coerced to a
different array type previously didn't perform checks.
- The set of domain constraints to be checked, is now evaluated once
during expression initialization, previously it was re-built
every time a domain check was evaluated. For normal queries this
doesn't change much, but e.g. for plpgsql functions, which caches
ExprStates, the old set could stick around longer. The behavior
around might still change.
Author: Andres Freund, with significant changes by Tom Lane,
changes by Heikki Linnakangas
Reviewed-By: Tom Lane, Heikki Linnakangas
Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
|
|
|
* prototypes from functions in execExpr.c
|
1996-07-09 08:22:35 +02:00
|
|
|
*/
|
Faster expression evaluation and targetlist projection.
This replaces the old, recursive tree-walk based evaluation, with
non-recursive, opcode dispatch based, expression evaluation.
Projection is now implemented as part of expression evaluation.
This both leads to significant performance improvements, and makes
future just-in-time compilation of expressions easier.
The speed gains primarily come from:
- non-recursive implementation reduces stack usage / overhead
- simple sub-expressions are implemented with a single jump, without
function calls
- sharing some state between different sub-expressions
- reduced amount of indirect/hard to predict memory accesses by laying
out operation metadata sequentially; including the avoidance of
nearly all of the previously used linked lists
- more code has been moved to expression initialization, avoiding
constant re-checks at evaluation time
Future just-in-time compilation (JIT) has become easier, as
demonstrated by released patches intended to be merged in a later
release, for primarily two reasons: Firstly, due to a stricter split
between expression initialization and evaluation, less code has to be
handled by the JIT. Secondly, due to the non-recursive nature of the
generated "instructions", less performance-critical code-paths can
easily be shared between interpreted and compiled evaluation.
The new framework allows for significant future optimizations. E.g.:
- basic infrastructure for to later reduce the per executor-startup
overhead of expression evaluation, by caching state in prepared
statements. That'd be helpful in OLTPish scenarios where
initialization overhead is measurable.
- optimizing the generated "code". A number of proposals for potential
work has already been made.
- optimizing the interpreter. Similarly a number of proposals have
been made here too.
The move of logic into the expression initialization step leads to some
backward-incompatible changes:
- Function permission checks are now done during expression
initialization, whereas previously they were done during
execution. In edge cases this can lead to errors being raised that
previously wouldn't have been, e.g. a NULL array being coerced to a
different array type previously didn't perform checks.
- The set of domain constraints to be checked, is now evaluated once
during expression initialization, previously it was re-built
every time a domain check was evaluated. For normal queries this
doesn't change much, but e.g. for plpgsql functions, which caches
ExprStates, the old set could stick around longer. The behavior
around might still change.
Author: Andres Freund, with significant changes by Tom Lane,
changes by Heikki Linnakangas
Reviewed-By: Tom Lane, Heikki Linnakangas
Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
|
|
|
extern ExprState *ExecInitExpr(Expr *node, PlanState *parent);
|
Rearrange execution of PARAM_EXTERN Params for plpgsql's benefit.
This patch does three interrelated things:
* Create a new expression execution step type EEOP_PARAM_CALLBACK
and add the infrastructure needed for add-on modules to generate that.
As discussed, the best control mechanism for that seems to be to add
another hook function to ParamListInfo, which will be called by
ExecInitExpr if it's supplied and a PARAM_EXTERN Param is found.
For stand-alone expressions, we add a new entry point to allow the
ParamListInfo to be specified directly, since it can't be retrieved
from the parent plan node's EState.
* Redesign the API for the ParamListInfo paramFetch hook so that the
ParamExternData array can be entirely virtual. This also lets us get rid
of ParamListInfo.paramMask, instead leaving it to the paramFetch hook to
decide which param IDs should be accessible or not. plpgsql_param_fetch
was already doing the identical masking check, so having callers do it too
seemed redundant. While I was at it, I added a "speculative" flag to
paramFetch that the planner can specify as TRUE to avoid unwanted failures.
This solves an ancient problem for plpgsql that it couldn't provide values
of non-DTYPE_VAR variables to the planner for fear of triggering premature
"record not assigned yet" or "field not found" errors during planning.
* Rework plpgsql to get rid of the need for "unshared" parameter lists,
by dint of turning the single ParamListInfo per estate into a nearly
read-only data structure that doesn't instantiate any per-variable data.
Instead, the paramFetch hook controls access to per-variable data and can
make the right decisions on the fly, replacing the cases that we used to
need multiple ParamListInfos for. This might perhaps have been a
performance loss on its own, but by using a paramCompile hook we can
bypass plpgsql_param_fetch entirely during normal query execution.
(It's now only called when, eg, we copy the ParamListInfo into a cursor
portal. copyParamList() or SerializeParamList() effectively instantiate
the virtual parameter array as a simple physical array without a
paramFetch hook, which is what we want in those cases.) This allows
reverting most of commit 6c82d8d1f, though I kept the cosmetic
code-consolidation aspects of that (eg the assign_simple_var function).
Performance testing shows this to be at worst a break-even change,
and it can provide wins ranging up to 20% in test cases involving
accesses to fields of "record" variables. The fact that values of
such variables can now be exposed to the planner might produce wins
in some situations, too, but I've not pursued that angle.
In passing, remove the "parent" pointer from the arguments to
ExecInitExprRec and related functions, instead storing that pointer in a
transient field in ExprState. The ParamListInfo pointer for a stand-alone
expression is handled the same way; we'd otherwise have had to add
yet another recursively-passed-down argument in expression compilation.
Discussion: https://postgr.es/m/32589.1513706441@sss.pgh.pa.us
2017-12-21 18:57:41 +01:00
|
|
|
extern ExprState *ExecInitExprWithParams(Expr *node, ParamListInfo ext_params);
|
Faster expression evaluation and targetlist projection.
This replaces the old, recursive tree-walk based evaluation, with
non-recursive, opcode dispatch based, expression evaluation.
Projection is now implemented as part of expression evaluation.
This both leads to significant performance improvements, and makes
future just-in-time compilation of expressions easier.
The speed gains primarily come from:
- non-recursive implementation reduces stack usage / overhead
- simple sub-expressions are implemented with a single jump, without
function calls
- sharing some state between different sub-expressions
- reduced amount of indirect/hard to predict memory accesses by laying
out operation metadata sequentially; including the avoidance of
nearly all of the previously used linked lists
- more code has been moved to expression initialization, avoiding
constant re-checks at evaluation time
Future just-in-time compilation (JIT) has become easier, as
demonstrated by released patches intended to be merged in a later
release, for primarily two reasons: Firstly, due to a stricter split
between expression initialization and evaluation, less code has to be
handled by the JIT. Secondly, due to the non-recursive nature of the
generated "instructions", less performance-critical code-paths can
easily be shared between interpreted and compiled evaluation.
The new framework allows for significant future optimizations. E.g.:
- basic infrastructure for to later reduce the per executor-startup
overhead of expression evaluation, by caching state in prepared
statements. That'd be helpful in OLTPish scenarios where
initialization overhead is measurable.
- optimizing the generated "code". A number of proposals for potential
work has already been made.
- optimizing the interpreter. Similarly a number of proposals have
been made here too.
The move of logic into the expression initialization step leads to some
backward-incompatible changes:
- Function permission checks are now done during expression
initialization, whereas previously they were done during
execution. In edge cases this can lead to errors being raised that
previously wouldn't have been, e.g. a NULL array being coerced to a
different array type previously didn't perform checks.
- The set of domain constraints to be checked, is now evaluated once
during expression initialization, previously it was re-built
every time a domain check was evaluated. For normal queries this
doesn't change much, but e.g. for plpgsql functions, which caches
ExprStates, the old set could stick around longer. The behavior
around might still change.
Author: Andres Freund, with significant changes by Tom Lane,
changes by Heikki Linnakangas
Reviewed-By: Tom Lane, Heikki Linnakangas
Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
|
|
|
extern ExprState *ExecInitQual(List *qual, PlanState *parent);
|
|
|
|
extern ExprState *ExecInitCheck(List *qual, PlanState *parent);
|
|
|
|
extern List *ExecInitExprList(List *nodes, PlanState *parent);
|
2018-01-09 22:25:38 +01:00
|
|
|
extern ExprState *ExecBuildAggTrans(AggState *aggstate, struct AggStatePerPhaseData *phase,
|
|
|
|
bool doSort, bool doHash);
|
2018-02-16 06:55:31 +01:00
|
|
|
extern ExprState *ExecBuildGroupingEqual(TupleDesc ldesc, TupleDesc rdesc,
|
|
|
|
int numCols,
|
|
|
|
AttrNumber *keyColIdx,
|
|
|
|
Oid *eqfunctions,
|
|
|
|
PlanState *parent);
|
Faster expression evaluation and targetlist projection.
This replaces the old, recursive tree-walk based evaluation, with
non-recursive, opcode dispatch based, expression evaluation.
Projection is now implemented as part of expression evaluation.
This both leads to significant performance improvements, and makes
future just-in-time compilation of expressions easier.
The speed gains primarily come from:
- non-recursive implementation reduces stack usage / overhead
- simple sub-expressions are implemented with a single jump, without
function calls
- sharing some state between different sub-expressions
- reduced amount of indirect/hard to predict memory accesses by laying
out operation metadata sequentially; including the avoidance of
nearly all of the previously used linked lists
- more code has been moved to expression initialization, avoiding
constant re-checks at evaluation time
Future just-in-time compilation (JIT) has become easier, as
demonstrated by released patches intended to be merged in a later
release, for primarily two reasons: Firstly, due to a stricter split
between expression initialization and evaluation, less code has to be
handled by the JIT. Secondly, due to the non-recursive nature of the
generated "instructions", less performance-critical code-paths can
easily be shared between interpreted and compiled evaluation.
The new framework allows for significant future optimizations. E.g.:
- basic infrastructure for to later reduce the per executor-startup
overhead of expression evaluation, by caching state in prepared
statements. That'd be helpful in OLTPish scenarios where
initialization overhead is measurable.
- optimizing the generated "code". A number of proposals for potential
work has already been made.
- optimizing the interpreter. Similarly a number of proposals have
been made here too.
The move of logic into the expression initialization step leads to some
backward-incompatible changes:
- Function permission checks are now done during expression
initialization, whereas previously they were done during
execution. In edge cases this can lead to errors being raised that
previously wouldn't have been, e.g. a NULL array being coerced to a
different array type previously didn't perform checks.
- The set of domain constraints to be checked, is now evaluated once
during expression initialization, previously it was re-built
every time a domain check was evaluated. For normal queries this
doesn't change much, but e.g. for plpgsql functions, which caches
ExprStates, the old set could stick around longer. The behavior
around might still change.
Author: Andres Freund, with significant changes by Tom Lane,
changes by Heikki Linnakangas
Reviewed-By: Tom Lane, Heikki Linnakangas
Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
|
|
|
extern ProjectionInfo *ExecBuildProjectionInfo(List *targetList,
|
|
|
|
ExprContext *econtext,
|
|
|
|
TupleTableSlot *slot,
|
|
|
|
PlanState *parent,
|
|
|
|
TupleDesc inputDesc);
|
|
|
|
extern ExprState *ExecPrepareExpr(Expr *node, EState *estate);
|
|
|
|
extern ExprState *ExecPrepareQual(List *qual, EState *estate);
|
|
|
|
extern ExprState *ExecPrepareCheck(List *qual, EState *estate);
|
|
|
|
extern List *ExecPrepareExprList(List *nodes, EState *estate);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* ExecEvalExpr
|
|
|
|
*
|
|
|
|
* Evaluate expression identified by "state" in the execution context
|
|
|
|
* given by "econtext". *isNull is set to the is-null flag for the result,
|
|
|
|
* and the Datum value is the function result.
|
|
|
|
*
|
|
|
|
* The caller should already have switched into the temporary memory
|
|
|
|
* context econtext->ecxt_per_tuple_memory. The convenience entry point
|
|
|
|
* ExecEvalExprSwitchContext() is provided for callers who don't prefer to
|
|
|
|
* do the switch in an outer loop.
|
|
|
|
*/
|
|
|
|
#ifndef FRONTEND
|
|
|
|
static inline Datum
|
|
|
|
ExecEvalExpr(ExprState *state,
|
|
|
|
ExprContext *econtext,
|
|
|
|
bool *isNull)
|
|
|
|
{
|
2017-09-07 18:06:23 +02:00
|
|
|
return state->evalfunc(state, econtext, isNull);
|
Faster expression evaluation and targetlist projection.
This replaces the old, recursive tree-walk based evaluation, with
non-recursive, opcode dispatch based, expression evaluation.
Projection is now implemented as part of expression evaluation.
This both leads to significant performance improvements, and makes
future just-in-time compilation of expressions easier.
The speed gains primarily come from:
- non-recursive implementation reduces stack usage / overhead
- simple sub-expressions are implemented with a single jump, without
function calls
- sharing some state between different sub-expressions
- reduced amount of indirect/hard to predict memory accesses by laying
out operation metadata sequentially; including the avoidance of
nearly all of the previously used linked lists
- more code has been moved to expression initialization, avoiding
constant re-checks at evaluation time
Future just-in-time compilation (JIT) has become easier, as
demonstrated by released patches intended to be merged in a later
release, for primarily two reasons: Firstly, due to a stricter split
between expression initialization and evaluation, less code has to be
handled by the JIT. Secondly, due to the non-recursive nature of the
generated "instructions", less performance-critical code-paths can
easily be shared between interpreted and compiled evaluation.
The new framework allows for significant future optimizations. E.g.:
- basic infrastructure for to later reduce the per executor-startup
overhead of expression evaluation, by caching state in prepared
statements. That'd be helpful in OLTPish scenarios where
initialization overhead is measurable.
- optimizing the generated "code". A number of proposals for potential
work has already been made.
- optimizing the interpreter. Similarly a number of proposals have
been made here too.
The move of logic into the expression initialization step leads to some
backward-incompatible changes:
- Function permission checks are now done during expression
initialization, whereas previously they were done during
execution. In edge cases this can lead to errors being raised that
previously wouldn't have been, e.g. a NULL array being coerced to a
different array type previously didn't perform checks.
- The set of domain constraints to be checked, is now evaluated once
during expression initialization, previously it was re-built
every time a domain check was evaluated. For normal queries this
doesn't change much, but e.g. for plpgsql functions, which caches
ExprStates, the old set could stick around longer. The behavior
around might still change.
Author: Andres Freund, with significant changes by Tom Lane,
changes by Heikki Linnakangas
Reviewed-By: Tom Lane, Heikki Linnakangas
Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/*
|
|
|
|
* ExecEvalExprSwitchContext
|
|
|
|
*
|
|
|
|
* Same as ExecEvalExpr, but get into the right allocation context explicitly.
|
|
|
|
*/
|
|
|
|
#ifndef FRONTEND
|
|
|
|
static inline Datum
|
|
|
|
ExecEvalExprSwitchContext(ExprState *state,
|
|
|
|
ExprContext *econtext,
|
|
|
|
bool *isNull)
|
|
|
|
{
|
|
|
|
Datum retDatum;
|
|
|
|
MemoryContext oldContext;
|
|
|
|
|
|
|
|
oldContext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
|
2017-09-07 18:06:23 +02:00
|
|
|
retDatum = state->evalfunc(state, econtext, isNull);
|
Faster expression evaluation and targetlist projection.
This replaces the old, recursive tree-walk based evaluation, with
non-recursive, opcode dispatch based, expression evaluation.
Projection is now implemented as part of expression evaluation.
This both leads to significant performance improvements, and makes
future just-in-time compilation of expressions easier.
The speed gains primarily come from:
- non-recursive implementation reduces stack usage / overhead
- simple sub-expressions are implemented with a single jump, without
function calls
- sharing some state between different sub-expressions
- reduced amount of indirect/hard to predict memory accesses by laying
out operation metadata sequentially; including the avoidance of
nearly all of the previously used linked lists
- more code has been moved to expression initialization, avoiding
constant re-checks at evaluation time
Future just-in-time compilation (JIT) has become easier, as
demonstrated by released patches intended to be merged in a later
release, for primarily two reasons: Firstly, due to a stricter split
between expression initialization and evaluation, less code has to be
handled by the JIT. Secondly, due to the non-recursive nature of the
generated "instructions", less performance-critical code-paths can
easily be shared between interpreted and compiled evaluation.
The new framework allows for significant future optimizations. E.g.:
- basic infrastructure for to later reduce the per executor-startup
overhead of expression evaluation, by caching state in prepared
statements. That'd be helpful in OLTPish scenarios where
initialization overhead is measurable.
- optimizing the generated "code". A number of proposals for potential
work has already been made.
- optimizing the interpreter. Similarly a number of proposals have
been made here too.
The move of logic into the expression initialization step leads to some
backward-incompatible changes:
- Function permission checks are now done during expression
initialization, whereas previously they were done during
execution. In edge cases this can lead to errors being raised that
previously wouldn't have been, e.g. a NULL array being coerced to a
different array type previously didn't perform checks.
- The set of domain constraints to be checked, is now evaluated once
during expression initialization, previously it was re-built
every time a domain check was evaluated. For normal queries this
doesn't change much, but e.g. for plpgsql functions, which caches
ExprStates, the old set could stick around longer. The behavior
around might still change.
Author: Andres Freund, with significant changes by Tom Lane,
changes by Heikki Linnakangas
Reviewed-By: Tom Lane, Heikki Linnakangas
Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
|
|
|
MemoryContextSwitchTo(oldContext);
|
|
|
|
return retDatum;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/*
|
|
|
|
* ExecProject
|
|
|
|
*
|
|
|
|
* Projects a tuple based on projection info and stores it in the slot passed
|
|
|
|
* to ExecBuildProjectInfo().
|
|
|
|
*
|
|
|
|
* Note: the result is always a virtual tuple; therefore it may reference
|
|
|
|
* the contents of the exprContext's scan tuples and/or temporary results
|
|
|
|
* constructed in the exprContext. If the caller wishes the result to be
|
|
|
|
* valid longer than that data will be valid, he must call ExecMaterializeSlot
|
|
|
|
* on the result slot.
|
|
|
|
*/
|
|
|
|
#ifndef FRONTEND
|
|
|
|
static inline TupleTableSlot *
|
|
|
|
ExecProject(ProjectionInfo *projInfo)
|
|
|
|
{
|
|
|
|
ExprContext *econtext = projInfo->pi_exprContext;
|
|
|
|
ExprState *state = &projInfo->pi_state;
|
|
|
|
TupleTableSlot *slot = state->resultslot;
|
|
|
|
bool isnull;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Clear any former contents of the result slot. This makes it safe for
|
|
|
|
* us to use the slot's Datum/isnull arrays as workspace.
|
|
|
|
*/
|
|
|
|
ExecClearTuple(slot);
|
|
|
|
|
|
|
|
/* Run the expression, discarding scalar result from the last column. */
|
|
|
|
(void) ExecEvalExprSwitchContext(state, econtext, &isnull);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Successfully formed a result row. Mark the result slot as containing a
|
|
|
|
* valid virtual tuple (inlined version of ExecStoreVirtualTuple()).
|
|
|
|
*/
|
2018-10-16 00:24:33 +02:00
|
|
|
slot->tts_flags &= ~TTS_FLAG_EMPTY;
|
Faster expression evaluation and targetlist projection.
This replaces the old, recursive tree-walk based evaluation, with
non-recursive, opcode dispatch based, expression evaluation.
Projection is now implemented as part of expression evaluation.
This both leads to significant performance improvements, and makes
future just-in-time compilation of expressions easier.
The speed gains primarily come from:
- non-recursive implementation reduces stack usage / overhead
- simple sub-expressions are implemented with a single jump, without
function calls
- sharing some state between different sub-expressions
- reduced amount of indirect/hard to predict memory accesses by laying
out operation metadata sequentially; including the avoidance of
nearly all of the previously used linked lists
- more code has been moved to expression initialization, avoiding
constant re-checks at evaluation time
Future just-in-time compilation (JIT) has become easier, as
demonstrated by released patches intended to be merged in a later
release, for primarily two reasons: Firstly, due to a stricter split
between expression initialization and evaluation, less code has to be
handled by the JIT. Secondly, due to the non-recursive nature of the
generated "instructions", less performance-critical code-paths can
easily be shared between interpreted and compiled evaluation.
The new framework allows for significant future optimizations. E.g.:
- basic infrastructure for to later reduce the per executor-startup
overhead of expression evaluation, by caching state in prepared
statements. That'd be helpful in OLTPish scenarios where
initialization overhead is measurable.
- optimizing the generated "code". A number of proposals for potential
work has already been made.
- optimizing the interpreter. Similarly a number of proposals have
been made here too.
The move of logic into the expression initialization step leads to some
backward-incompatible changes:
- Function permission checks are now done during expression
initialization, whereas previously they were done during
execution. In edge cases this can lead to errors being raised that
previously wouldn't have been, e.g. a NULL array being coerced to a
different array type previously didn't perform checks.
- The set of domain constraints to be checked, is now evaluated once
during expression initialization, previously it was re-built
every time a domain check was evaluated. For normal queries this
doesn't change much, but e.g. for plpgsql functions, which caches
ExprStates, the old set could stick around longer. The behavior
around might still change.
Author: Andres Freund, with significant changes by Tom Lane,
changes by Heikki Linnakangas
Reviewed-By: Tom Lane, Heikki Linnakangas
Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
|
|
|
slot->tts_nvalid = slot->tts_tupleDescriptor->natts;
|
|
|
|
|
|
|
|
return slot;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/*
|
|
|
|
* ExecQual - evaluate a qual prepared with ExecInitQual (possibly via
|
|
|
|
* ExecPrepareQual). Returns true if qual is satisfied, else false.
|
|
|
|
*
|
|
|
|
* Note: ExecQual used to have a third argument "resultForNull". The
|
|
|
|
* behavior of this function now corresponds to resultForNull == false.
|
|
|
|
* If you want the resultForNull == true behavior, see ExecCheck.
|
|
|
|
*/
|
|
|
|
#ifndef FRONTEND
|
|
|
|
static inline bool
|
|
|
|
ExecQual(ExprState *state, ExprContext *econtext)
|
|
|
|
{
|
|
|
|
Datum ret;
|
|
|
|
bool isnull;
|
|
|
|
|
|
|
|
/* short-circuit (here and in ExecInitQual) for empty restriction list */
|
|
|
|
if (state == NULL)
|
|
|
|
return true;
|
|
|
|
|
|
|
|
/* verify that expression was compiled using ExecInitQual */
|
|
|
|
Assert(state->flags & EEO_FLAG_IS_QUAL);
|
|
|
|
|
|
|
|
ret = ExecEvalExprSwitchContext(state, econtext, &isnull);
|
|
|
|
|
|
|
|
/* EEOP_QUAL should never return NULL */
|
|
|
|
Assert(!isnull);
|
|
|
|
|
|
|
|
return DatumGetBool(ret);
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
2018-01-29 21:16:53 +01:00
|
|
|
/*
|
|
|
|
* ExecQualAndReset() - evaluate qual with ExecQual() and reset expression
|
|
|
|
* context.
|
|
|
|
*/
|
|
|
|
#ifndef FRONTEND
|
|
|
|
static inline bool
|
|
|
|
ExecQualAndReset(ExprState *state, ExprContext *econtext)
|
|
|
|
{
|
|
|
|
bool ret = ExecQual(state, econtext);
|
|
|
|
|
|
|
|
/* inline ResetExprContext, to avoid ordering issue in this file */
|
|
|
|
MemoryContextReset(econtext->ecxt_per_tuple_memory);
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
Faster expression evaluation and targetlist projection.
This replaces the old, recursive tree-walk based evaluation, with
non-recursive, opcode dispatch based, expression evaluation.
Projection is now implemented as part of expression evaluation.
This both leads to significant performance improvements, and makes
future just-in-time compilation of expressions easier.
The speed gains primarily come from:
- non-recursive implementation reduces stack usage / overhead
- simple sub-expressions are implemented with a single jump, without
function calls
- sharing some state between different sub-expressions
- reduced amount of indirect/hard to predict memory accesses by laying
out operation metadata sequentially; including the avoidance of
nearly all of the previously used linked lists
- more code has been moved to expression initialization, avoiding
constant re-checks at evaluation time
Future just-in-time compilation (JIT) has become easier, as
demonstrated by released patches intended to be merged in a later
release, for primarily two reasons: Firstly, due to a stricter split
between expression initialization and evaluation, less code has to be
handled by the JIT. Secondly, due to the non-recursive nature of the
generated "instructions", less performance-critical code-paths can
easily be shared between interpreted and compiled evaluation.
The new framework allows for significant future optimizations. E.g.:
- basic infrastructure for to later reduce the per executor-startup
overhead of expression evaluation, by caching state in prepared
statements. That'd be helpful in OLTPish scenarios where
initialization overhead is measurable.
- optimizing the generated "code". A number of proposals for potential
work has already been made.
- optimizing the interpreter. Similarly a number of proposals have
been made here too.
The move of logic into the expression initialization step leads to some
backward-incompatible changes:
- Function permission checks are now done during expression
initialization, whereas previously they were done during
execution. In edge cases this can lead to errors being raised that
previously wouldn't have been, e.g. a NULL array being coerced to a
different array type previously didn't perform checks.
- The set of domain constraints to be checked, is now evaluated once
during expression initialization, previously it was re-built
every time a domain check was evaluated. For normal queries this
doesn't change much, but e.g. for plpgsql functions, which caches
ExprStates, the old set could stick around longer. The behavior
around might still change.
Author: Andres Freund, with significant changes by Tom Lane,
changes by Heikki Linnakangas
Reviewed-By: Tom Lane, Heikki Linnakangas
Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
|
|
|
extern bool ExecCheck(ExprState *state, ExprContext *context);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* prototypes from functions in execSRF.c
|
|
|
|
*/
|
|
|
|
extern SetExprState *ExecInitTableFunctionResult(Expr *expr,
|
|
|
|
ExprContext *econtext, PlanState *parent);
|
|
|
|
extern Tuplestorestate *ExecMakeTableFunctionResult(SetExprState *setexpr,
|
2002-09-04 22:31:48 +02:00
|
|
|
ExprContext *econtext,
|
2014-06-20 04:13:41 +02:00
|
|
|
MemoryContext argContext,
|
2008-10-29 01:00:39 +01:00
|
|
|
TupleDesc expectedDesc,
|
|
|
|
bool randomAccess);
|
Faster expression evaluation and targetlist projection.
This replaces the old, recursive tree-walk based evaluation, with
non-recursive, opcode dispatch based, expression evaluation.
Projection is now implemented as part of expression evaluation.
This both leads to significant performance improvements, and makes
future just-in-time compilation of expressions easier.
The speed gains primarily come from:
- non-recursive implementation reduces stack usage / overhead
- simple sub-expressions are implemented with a single jump, without
function calls
- sharing some state between different sub-expressions
- reduced amount of indirect/hard to predict memory accesses by laying
out operation metadata sequentially; including the avoidance of
nearly all of the previously used linked lists
- more code has been moved to expression initialization, avoiding
constant re-checks at evaluation time
Future just-in-time compilation (JIT) has become easier, as
demonstrated by released patches intended to be merged in a later
release, for primarily two reasons: Firstly, due to a stricter split
between expression initialization and evaluation, less code has to be
handled by the JIT. Secondly, due to the non-recursive nature of the
generated "instructions", less performance-critical code-paths can
easily be shared between interpreted and compiled evaluation.
The new framework allows for significant future optimizations. E.g.:
- basic infrastructure for to later reduce the per executor-startup
overhead of expression evaluation, by caching state in prepared
statements. That'd be helpful in OLTPish scenarios where
initialization overhead is measurable.
- optimizing the generated "code". A number of proposals for potential
work has already been made.
- optimizing the interpreter. Similarly a number of proposals have
been made here too.
The move of logic into the expression initialization step leads to some
backward-incompatible changes:
- Function permission checks are now done during expression
initialization, whereas previously they were done during
execution. In edge cases this can lead to errors being raised that
previously wouldn't have been, e.g. a NULL array being coerced to a
different array type previously didn't perform checks.
- The set of domain constraints to be checked, is now evaluated once
during expression initialization, previously it was re-built
every time a domain check was evaluated. For normal queries this
doesn't change much, but e.g. for plpgsql functions, which caches
ExprStates, the old set could stick around longer. The behavior
around might still change.
Author: Andres Freund, with significant changes by Tom Lane,
changes by Heikki Linnakangas
Reviewed-By: Tom Lane, Heikki Linnakangas
Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
|
|
|
extern SetExprState *ExecInitFunctionResultSet(Expr *expr,
|
|
|
|
ExprContext *econtext, PlanState *parent);
|
|
|
|
extern Datum ExecMakeFunctionResultSet(SetExprState *fcache,
|
Move targetlist SRF handling from expression evaluation to new executor node.
Evaluation of set returning functions (SRFs_ in the targetlist (like SELECT
generate_series(1,5)) so far was done in the expression evaluation (i.e.
ExecEvalExpr()) and projection (i.e. ExecProject/ExecTargetList) code.
This meant that most executor nodes performing projection, and most
expression evaluation functions, had to deal with the possibility that an
evaluated expression could return a set of return values.
That's bad because it leads to repeated code in a lot of places. It also,
and that's my (Andres's) motivation, made it a lot harder to implement a
more efficient way of doing expression evaluation.
To fix this, introduce a new executor node (ProjectSet) that can evaluate
targetlists containing one or more SRFs. To avoid the complexity of the old
way of handling nested expressions returning sets (e.g. having to pass up
ExprDoneCond, and dealing with arguments to functions returning sets etc.),
those SRFs can only be at the top level of the node's targetlist. The
planner makes sure (via split_pathtarget_at_srfs()) that SRF evaluation is
only necessary in ProjectSet nodes and that SRFs are only present at the
top level of the node's targetlist. If there are nested SRFs the planner
creates multiple stacked ProjectSet nodes. The ProjectSet nodes always get
input from an underlying node.
We also discussed and prototyped evaluating targetlist SRFs using ROWS
FROM(), but that turned out to be more complicated than we'd hoped.
While moving SRF evaluation to ProjectSet would allow to retain the old
"least common multiple" behavior when multiple SRFs are present in one
targetlist (i.e. continue returning rows until all SRFs are at the end of
their input at the same time), we decided to instead only return rows till
all SRFs are exhausted, returning NULL for already exhausted ones. We
deemed the previous behavior to be too confusing, unexpected and actually
not particularly useful.
As a side effect, the previously prohibited case of multiple set returning
arguments to a function, is now allowed. Not because it's particularly
desirable, but because it ends up working and there seems to be no argument
for adding code to prohibit it.
Currently the behavior for COALESCE and CASE containing SRFs has changed,
returning multiple rows from the expression, even when the SRF containing
"arm" of the expression is not evaluated. That's because the SRFs are
evaluated in a separate ProjectSet node. As that's quite confusing, we're
likely to instead prohibit SRFs in those places. But that's still being
discussed, and the code would reside in places not touched here, so that's
a task for later.
There's a lot of, now superfluous, code dealing with set return expressions
around. But as the changes to get rid of those are verbose largely boring,
it seems better for readability to keep the cleanup as a separate commit.
Author: Tom Lane and Andres Freund
Discussion: https://postgr.es/m/20160822214023.aaxz5l4igypowyri@alap3.anarazel.de
2017-01-18 21:46:50 +01:00
|
|
|
ExprContext *econtext,
|
2017-10-09 00:08:25 +02:00
|
|
|
MemoryContext argContext,
|
Move targetlist SRF handling from expression evaluation to new executor node.
Evaluation of set returning functions (SRFs_ in the targetlist (like SELECT
generate_series(1,5)) so far was done in the expression evaluation (i.e.
ExecEvalExpr()) and projection (i.e. ExecProject/ExecTargetList) code.
This meant that most executor nodes performing projection, and most
expression evaluation functions, had to deal with the possibility that an
evaluated expression could return a set of return values.
That's bad because it leads to repeated code in a lot of places. It also,
and that's my (Andres's) motivation, made it a lot harder to implement a
more efficient way of doing expression evaluation.
To fix this, introduce a new executor node (ProjectSet) that can evaluate
targetlists containing one or more SRFs. To avoid the complexity of the old
way of handling nested expressions returning sets (e.g. having to pass up
ExprDoneCond, and dealing with arguments to functions returning sets etc.),
those SRFs can only be at the top level of the node's targetlist. The
planner makes sure (via split_pathtarget_at_srfs()) that SRF evaluation is
only necessary in ProjectSet nodes and that SRFs are only present at the
top level of the node's targetlist. If there are nested SRFs the planner
creates multiple stacked ProjectSet nodes. The ProjectSet nodes always get
input from an underlying node.
We also discussed and prototyped evaluating targetlist SRFs using ROWS
FROM(), but that turned out to be more complicated than we'd hoped.
While moving SRF evaluation to ProjectSet would allow to retain the old
"least common multiple" behavior when multiple SRFs are present in one
targetlist (i.e. continue returning rows until all SRFs are at the end of
their input at the same time), we decided to instead only return rows till
all SRFs are exhausted, returning NULL for already exhausted ones. We
deemed the previous behavior to be too confusing, unexpected and actually
not particularly useful.
As a side effect, the previously prohibited case of multiple set returning
arguments to a function, is now allowed. Not because it's particularly
desirable, but because it ends up working and there seems to be no argument
for adding code to prohibit it.
Currently the behavior for COALESCE and CASE containing SRFs has changed,
returning multiple rows from the expression, even when the SRF containing
"arm" of the expression is not evaluated. That's because the SRFs are
evaluated in a separate ProjectSet node. As that's quite confusing, we're
likely to instead prohibit SRFs in those places. But that's still being
discussed, and the code would reside in places not touched here, so that's
a task for later.
There's a lot of, now superfluous, code dealing with set return expressions
around. But as the changes to get rid of those are verbose largely boring,
it seems better for readability to keep the cleanup as a separate commit.
Author: Tom Lane and Andres Freund
Discussion: https://postgr.es/m/20160822214023.aaxz5l4igypowyri@alap3.anarazel.de
2017-01-18 21:46:50 +01:00
|
|
|
bool *isNull,
|
|
|
|
ExprDoneCond *isDone);
|
1996-07-09 08:22:35 +02:00
|
|
|
|
|
|
|
/*
|
|
|
|
* prototypes from functions in execScan.c
|
|
|
|
*/
|
2003-08-08 23:42:59 +02:00
|
|
|
typedef TupleTableSlot *(*ExecScanAccessMtd) (ScanState *node);
|
Re-implement EvalPlanQual processing to improve its performance and eliminate
a lot of strange behaviors that occurred in join cases. We now identify the
"current" row for every joined relation in UPDATE, DELETE, and SELECT FOR
UPDATE/SHARE queries. If an EvalPlanQual recheck is necessary, we jam the
appropriate row into each scan node in the rechecking plan, forcing it to emit
only that one row. The former behavior could rescan the whole of each joined
relation for each recheck, which was terrible for performance, and what's much
worse could result in duplicated output tuples.
Also, the original implementation of EvalPlanQual could not re-use the recheck
execution tree --- it had to go through a full executor init and shutdown for
every row to be tested. To avoid this overhead, I've associated a special
runtime Param with each LockRows or ModifyTable plan node, and arranged to
make every scan node below such a node depend on that Param. Thus, by
signaling a change in that Param, the EPQ machinery can just rescan the
already-built test plan.
This patch also adds a prohibition on set-returning functions in the
targetlist of SELECT FOR UPDATE/SHARE. This is needed to avoid the
duplicate-output-tuple problem. It seems fairly reasonable since the
other restrictions on SELECT FOR UPDATE are meant to ensure that there
is a unique correspondence between source tuples and result tuples,
which an output SRF destroys as much as anything else does.
2009-10-26 03:26:45 +01:00
|
|
|
typedef bool (*ExecScanRecheckMtd) (ScanState *node, TupleTableSlot *slot);
|
2000-07-12 04:37:39 +02:00
|
|
|
|
Re-implement EvalPlanQual processing to improve its performance and eliminate
a lot of strange behaviors that occurred in join cases. We now identify the
"current" row for every joined relation in UPDATE, DELETE, and SELECT FOR
UPDATE/SHARE queries. If an EvalPlanQual recheck is necessary, we jam the
appropriate row into each scan node in the rechecking plan, forcing it to emit
only that one row. The former behavior could rescan the whole of each joined
relation for each recheck, which was terrible for performance, and what's much
worse could result in duplicated output tuples.
Also, the original implementation of EvalPlanQual could not re-use the recheck
execution tree --- it had to go through a full executor init and shutdown for
every row to be tested. To avoid this overhead, I've associated a special
runtime Param with each LockRows or ModifyTable plan node, and arranged to
make every scan node below such a node depend on that Param. Thus, by
signaling a change in that Param, the EPQ machinery can just rescan the
already-built test plan.
This patch also adds a prohibition on set-returning functions in the
targetlist of SELECT FOR UPDATE/SHARE. This is needed to avoid the
duplicate-output-tuple problem. It seems fairly reasonable since the
other restrictions on SELECT FOR UPDATE are meant to ensure that there
is a unique correspondence between source tuples and result tuples,
which an output SRF destroys as much as anything else does.
2009-10-26 03:26:45 +01:00
|
|
|
extern TupleTableSlot *ExecScan(ScanState *node, ExecScanAccessMtd accessMtd,
|
2010-02-26 03:01:40 +01:00
|
|
|
ExecScanRecheckMtd recheckMtd);
|
2003-08-08 23:42:59 +02:00
|
|
|
extern void ExecAssignScanProjectionInfo(ScanState *node);
|
Code review for foreign/custom join pushdown patch.
Commit e7cb7ee14555cc9c5773e2c102efd6371f6f2005 included some design
decisions that seem pretty questionable to me, and there was quite a lot
of stuff not to like about the documentation and comments. Clean up
as follows:
* Consider foreign joins only between foreign tables on the same server,
rather than between any two foreign tables with the same underlying FDW
handler function. In most if not all cases, the FDW would simply have had
to apply the same-server restriction itself (far more expensively, both for
lack of caching and because it would be repeated for each combination of
input sub-joins), or else risk nasty bugs. Anyone who's really intent on
doing something outside this restriction can always use the
set_join_pathlist_hook.
* Rename fdw_ps_tlist/custom_ps_tlist to fdw_scan_tlist/custom_scan_tlist
to better reflect what they're for, and allow these custom scan tlists
to be used even for base relations.
* Change make_foreignscan() API to include passing the fdw_scan_tlist
value, since the FDW is required to set that. Backwards compatibility
doesn't seem like an adequate reason to expect FDWs to set it in some
ad-hoc extra step, and anyway existing FDWs can just pass NIL.
* Change the API of path-generating subroutines of add_paths_to_joinrel,
and in particular that of GetForeignJoinPaths and set_join_pathlist_hook,
so that various less-used parameters are passed in a struct rather than
as separate parameter-list entries. The objective here is to reduce the
probability that future additions to those parameter lists will result in
source-level API breaks for users of these hooks. It's possible that this
is even a small win for the core code, since most CPU architectures can't
pass more than half a dozen parameters efficiently anyway. I kept root,
joinrel, outerrel, innerrel, and jointype as separate parameters to reduce
code churn in joinpath.c --- in particular, putting jointype into the
struct would have been problematic because of the subroutines' habit of
changing their local copies of that variable.
* Avoid ad-hocery in ExecAssignScanProjectionInfo. It was probably all
right for it to know about IndexOnlyScan, but if the list is to grow
we should refactor the knowledge out to the callers.
* Restore nodeForeignscan.c's previous use of the relcache to avoid
extra GetFdwRoutine lookups for base-relation scans.
* Lots of cleanup of documentation and missed comments. Re-order some
code additions into more logical places.
2015-05-10 20:36:30 +02:00
|
|
|
extern void ExecAssignScanProjectionInfoWithVarno(ScanState *node, Index varno);
|
Re-implement EvalPlanQual processing to improve its performance and eliminate
a lot of strange behaviors that occurred in join cases. We now identify the
"current" row for every joined relation in UPDATE, DELETE, and SELECT FOR
UPDATE/SHARE queries. If an EvalPlanQual recheck is necessary, we jam the
appropriate row into each scan node in the rechecking plan, forcing it to emit
only that one row. The former behavior could rescan the whole of each joined
relation for each recheck, which was terrible for performance, and what's much
worse could result in duplicated output tuples.
Also, the original implementation of EvalPlanQual could not re-use the recheck
execution tree --- it had to go through a full executor init and shutdown for
every row to be tested. To avoid this overhead, I've associated a special
runtime Param with each LockRows or ModifyTable plan node, and arranged to
make every scan node below such a node depend on that Param. Thus, by
signaling a change in that Param, the EPQ machinery can just rescan the
already-built test plan.
This patch also adds a prohibition on set-returning functions in the
targetlist of SELECT FOR UPDATE/SHARE. This is needed to avoid the
duplicate-output-tuple problem. It seems fairly reasonable since the
other restrictions on SELECT FOR UPDATE are meant to ensure that there
is a unique correspondence between source tuples and result tuples,
which an output SRF destroys as much as anything else does.
2009-10-26 03:26:45 +01:00
|
|
|
extern void ExecScanReScan(ScanState *node);
|
1996-07-09 08:22:35 +02:00
|
|
|
|
|
|
|
/*
|
|
|
|
* prototypes from functions in execTuples.c
|
|
|
|
*/
|
Don't require return slots for nodes without projection.
In a lot of nodes the return slot is not required. That can either be
because the node doesn't do any projection (say an Append node), or
because the node does perform projections but the projection is
optimized away because the projection would yield an identical row.
Slots aren't that small, especially for wide rows, so it's worthwhile
to avoid creating them. It's not possible to just skip creating the
slot - it's currently used to determine the tuple descriptor returned
by ExecGetResultType(). So separate the determination of the result
type from the slot creation. The work previously done internally
ExecInitResultTupleSlotTL() can now also be done separately with
ExecInitResultTypeTL() and ExecInitResultSlot(). That way nodes that
aren't guaranteed to need a result slot, can use
ExecInitResultTypeTL() to determine the result type of the node, and
ExecAssignScanProjectionInfo() (via
ExecConditionalAssignProjectionInfo()) determines that a result slot
is needed, it is created with ExecInitResultSlot().
Besides the advantage of avoiding to create slots that then are
unused, this is necessary preparation for later patches around tuple
table slot abstraction. In particular separating the return descriptor
and slot is a prerequisite to allow JITing of tuple deforming with
knowledge of the underlying tuple format, and to avoid unnecessarily
creating JITed tuple deforming for virtual slots.
This commit removes a redundant argument from
ExecInitResultTupleSlotTL(). While this commit touches a lot of the
relevant lines anyway, it'd normally still not worthwhile to cause
breakage, except that aforementioned later commits will touch *all*
ExecInitResultTupleSlotTL() callers anyway (but fits worse
thematically).
Author: Andres Freund
Discussion: https://postgr.es/m/20181105210039.hh4vvi4vwoq5ba2q@alap3.anarazel.de
2018-11-10 02:19:39 +01:00
|
|
|
extern void ExecInitResultTypeTL(PlanState *planstate);
|
|
|
|
extern void ExecInitResultSlot(PlanState *planstate);
|
|
|
|
extern void ExecInitResultTupleSlotTL(PlanState *planstate);
|
2018-02-17 06:17:38 +01:00
|
|
|
extern void ExecInitScanTupleSlot(EState *estate, ScanState *scanstate, TupleDesc tupleDesc);
|
|
|
|
extern TupleTableSlot *ExecInitExtraTupleSlot(EState *estate,
|
2018-04-26 20:47:16 +02:00
|
|
|
TupleDesc tupleDesc);
|
2000-09-12 23:07:18 +02:00
|
|
|
extern TupleTableSlot *ExecInitNullTupleSlot(EState *estate,
|
2001-03-22 05:01:46 +01:00
|
|
|
TupleDesc tupType);
|
2002-09-02 03:05:06 +02:00
|
|
|
extern TupleDesc ExecTypeFromTL(List *targetList, bool hasoid);
|
2003-05-06 22:26:28 +02:00
|
|
|
extern TupleDesc ExecCleanTypeFromTL(List *targetList, bool hasoid);
|
Ensure that RowExprs and whole-row Vars produce the expected column names.
At one time it wasn't terribly important what column names were associated
with the fields of a composite Datum, but since the introduction of
operations like row_to_json(), it's important that looking up the rowtype
ID embedded in the Datum returns the column names that users would expect.
That did not work terribly well before this patch: you could get the column
names of the underlying table, or column aliases from any level of the
query, depending on minor details of the plan tree. You could even get
totally empty field names, which is disastrous for cases like row_to_json().
To fix this for whole-row Vars, look to the RTE referenced by the Var, and
make sure its column aliases are applied to the rowtype associated with
the result Datums. This is a tad scary because we might have to return
a transient RECORD type even though the Var is declared as having some
named rowtype. In principle it should be all right because the record
type will still be physically compatible with the named rowtype; but
I had to weaken one Assert in ExecEvalConvertRowtype, and there might be
third-party code containing similar assumptions.
Similarly, RowExprs have to be willing to override the column names coming
from a named composite result type and produce a RECORD when the column
aliases visible at the site of the RowExpr differ from the underlying
table's column names.
In passing, revert the decision made in commit 398f70ec070fe601 to add
an alias-list argument to ExecTypeFromExprList: better to provide that
functionality in a separate function. This also reverts most of the code
changes in d68581483564ec0f, which we don't need because we're no longer
depending on the tupdesc found in the child plan node's result slot to be
blessed.
Back-patch to 9.4, but not earlier, since this solution changes the results
in some cases that users might not have realized were buggy. We'll apply a
more restricted form of this patch in older branches.
2014-11-10 21:21:09 +01:00
|
|
|
extern TupleDesc ExecTypeFromExprList(List *exprList);
|
|
|
|
extern void ExecTypeSetColNames(TupleDesc typeInfo, List *namesList);
|
2003-08-08 23:42:59 +02:00
|
|
|
extern void UpdateChangedParamSet(PlanState *node, Bitmapset *newchg);
|
1996-07-09 08:22:35 +02:00
|
|
|
|
2002-07-20 07:49:28 +02:00
|
|
|
typedef struct TupOutputState
|
|
|
|
{
|
2005-03-16 22:38:10 +01:00
|
|
|
TupleTableSlot *slot;
|
2003-05-06 22:26:28 +02:00
|
|
|
DestReceiver *dest;
|
2002-07-20 07:49:28 +02:00
|
|
|
} TupOutputState;
|
|
|
|
|
2003-05-06 22:26:28 +02:00
|
|
|
extern TupOutputState *begin_tup_output_tupdesc(DestReceiver *dest,
|
2003-08-04 02:43:34 +02:00
|
|
|
TupleDesc tupdesc);
|
2009-07-22 19:00:23 +02:00
|
|
|
extern void do_tup_output(TupOutputState *tstate, Datum *values, bool *isnull);
|
2016-05-23 20:16:40 +02:00
|
|
|
extern void do_text_output_multiline(TupOutputState *tstate, const char *txt);
|
2002-07-20 07:49:28 +02:00
|
|
|
extern void end_tup_output(TupOutputState *tstate);
|
|
|
|
|
2002-08-29 02:17:06 +02:00
|
|
|
/*
|
|
|
|
* Write a single line of text given as a C string.
|
|
|
|
*
|
|
|
|
* Should only be used with a single-TEXT-attribute tupdesc.
|
|
|
|
*/
|
2009-07-22 19:00:23 +02:00
|
|
|
#define do_text_output_oneline(tstate, str_to_emit) \
|
2002-07-20 07:49:28 +02:00
|
|
|
do { \
|
2009-07-22 19:00:23 +02:00
|
|
|
Datum values_[1]; \
|
|
|
|
bool isnull_[1]; \
|
|
|
|
values_[0] = PointerGetDatum(cstring_to_text(str_to_emit)); \
|
|
|
|
isnull_[0] = false; \
|
|
|
|
do_tup_output(tstate, values_, isnull_); \
|
|
|
|
pfree(DatumGetPointer(values_[0])); \
|
2002-07-20 07:49:28 +02:00
|
|
|
} while (0)
|
|
|
|
|
|
|
|
|
1996-07-09 08:22:35 +02:00
|
|
|
/*
|
1999-04-16 23:27:23 +02:00
|
|
|
* prototypes from functions in execUtils.c
|
1996-07-09 08:22:35 +02:00
|
|
|
*/
|
2002-12-15 17:17:59 +01:00
|
|
|
extern EState *CreateExecutorState(void);
|
|
|
|
extern void FreeExecutorState(EState *estate);
|
|
|
|
extern ExprContext *CreateExprContext(EState *estate);
|
2006-08-04 23:33:36 +02:00
|
|
|
extern ExprContext *CreateStandaloneExprContext(void);
|
2009-07-18 21:15:42 +02:00
|
|
|
extern void FreeExprContext(ExprContext *econtext, bool isCommit);
|
2003-12-18 21:21:37 +01:00
|
|
|
extern void ReScanExprContext(ExprContext *econtext);
|
2000-07-12 04:37:39 +02:00
|
|
|
|
|
|
|
#define ResetExprContext(econtext) \
|
|
|
|
MemoryContextReset((econtext)->ecxt_per_tuple_memory)
|
|
|
|
|
2001-01-22 01:50:07 +01:00
|
|
|
extern ExprContext *MakePerTupleExprContext(EState *estate);
|
|
|
|
|
|
|
|
/* Get an EState's per-output-tuple exprcontext, making it if first use */
|
|
|
|
#define GetPerTupleExprContext(estate) \
|
|
|
|
((estate)->es_per_tuple_exprcontext ? \
|
|
|
|
(estate)->es_per_tuple_exprcontext : \
|
|
|
|
MakePerTupleExprContext(estate))
|
|
|
|
|
|
|
|
#define GetPerTupleMemoryContext(estate) \
|
|
|
|
(GetPerTupleExprContext(estate)->ecxt_per_tuple_memory)
|
|
|
|
|
|
|
|
/* Reset an EState's per-output-tuple exprcontext, if one's been created */
|
|
|
|
#define ResetPerTupleExprContext(estate) \
|
|
|
|
do { \
|
|
|
|
if ((estate)->es_per_tuple_exprcontext) \
|
|
|
|
ResetExprContext((estate)->es_per_tuple_exprcontext); \
|
|
|
|
} while (0)
|
|
|
|
|
2003-08-08 23:42:59 +02:00
|
|
|
extern void ExecAssignExprContext(EState *estate, PlanState *planstate);
|
|
|
|
extern TupleDesc ExecGetResultType(PlanState *planstate);
|
2007-02-02 01:07:03 +01:00
|
|
|
extern void ExecAssignProjectionInfo(PlanState *planstate,
|
2007-11-15 22:14:46 +01:00
|
|
|
TupleDesc inputDesc);
|
2017-11-25 16:49:17 +01:00
|
|
|
extern void ExecConditionalAssignProjectionInfo(PlanState *planstate,
|
|
|
|
TupleDesc inputDesc, Index varno);
|
2003-08-08 23:42:59 +02:00
|
|
|
extern void ExecFreeExprContext(PlanState *planstate);
|
2006-06-16 20:42:24 +02:00
|
|
|
extern void ExecAssignScanType(ScanState *scanstate, TupleDesc tupDesc);
|
2018-02-17 06:17:38 +01:00
|
|
|
extern void ExecCreateScanSlotFromOuterPlan(EState *estate, ScanState *scanstate);
|
2002-12-15 17:17:59 +01:00
|
|
|
|
2005-12-03 06:51:03 +01:00
|
|
|
extern bool ExecRelationIsTargetRelation(EState *estate, Index scanrelid);
|
|
|
|
|
2013-04-27 23:48:57 +02:00
|
|
|
extern Relation ExecOpenScanRelation(EState *estate, Index scanrelid, int eflags);
|
2018-10-04 20:03:37 +02:00
|
|
|
|
2018-10-04 21:48:17 +02:00
|
|
|
extern void ExecInitRangeTable(EState *estate, List *rangeTable);
|
|
|
|
|
|
|
|
static inline RangeTblEntry *
|
|
|
|
exec_rt_fetch(Index rti, EState *estate)
|
|
|
|
{
|
|
|
|
Assert(rti > 0 && rti <= estate->es_range_table_size);
|
|
|
|
return estate->es_range_table_array[rti - 1];
|
|
|
|
}
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2018-10-04 20:03:37 +02:00
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extern Relation ExecGetRangeTableRelation(EState *estate, Index rti);
|
2005-12-02 21:03:42 +01:00
|
|
|
|
2017-04-18 19:20:59 +02:00
|
|
|
extern int executor_errposition(EState *estate, int location);
|
|
|
|
|
2015-04-24 08:33:23 +02:00
|
|
|
extern void RegisterExprContextCallback(ExprContext *econtext,
|
|
|
|
ExprContextCallbackFunction function,
|
|
|
|
Datum arg);
|
|
|
|
extern void UnregisterExprContextCallback(ExprContext *econtext,
|
|
|
|
ExprContextCallbackFunction function,
|
|
|
|
Datum arg);
|
Faster expression evaluation and targetlist projection.
This replaces the old, recursive tree-walk based evaluation, with
non-recursive, opcode dispatch based, expression evaluation.
Projection is now implemented as part of expression evaluation.
This both leads to significant performance improvements, and makes
future just-in-time compilation of expressions easier.
The speed gains primarily come from:
- non-recursive implementation reduces stack usage / overhead
- simple sub-expressions are implemented with a single jump, without
function calls
- sharing some state between different sub-expressions
- reduced amount of indirect/hard to predict memory accesses by laying
out operation metadata sequentially; including the avoidance of
nearly all of the previously used linked lists
- more code has been moved to expression initialization, avoiding
constant re-checks at evaluation time
Future just-in-time compilation (JIT) has become easier, as
demonstrated by released patches intended to be merged in a later
release, for primarily two reasons: Firstly, due to a stricter split
between expression initialization and evaluation, less code has to be
handled by the JIT. Secondly, due to the non-recursive nature of the
generated "instructions", less performance-critical code-paths can
easily be shared between interpreted and compiled evaluation.
The new framework allows for significant future optimizations. E.g.:
- basic infrastructure for to later reduce the per executor-startup
overhead of expression evaluation, by caching state in prepared
statements. That'd be helpful in OLTPish scenarios where
initialization overhead is measurable.
- optimizing the generated "code". A number of proposals for potential
work has already been made.
- optimizing the interpreter. Similarly a number of proposals have
been made here too.
The move of logic into the expression initialization step leads to some
backward-incompatible changes:
- Function permission checks are now done during expression
initialization, whereas previously they were done during
execution. In edge cases this can lead to errors being raised that
previously wouldn't have been, e.g. a NULL array being coerced to a
different array type previously didn't perform checks.
- The set of domain constraints to be checked, is now evaluated once
during expression initialization, previously it was re-built
every time a domain check was evaluated. For normal queries this
doesn't change much, but e.g. for plpgsql functions, which caches
ExprStates, the old set could stick around longer. The behavior
around might still change.
Author: Andres Freund, with significant changes by Tom Lane,
changes by Heikki Linnakangas
Reviewed-By: Tom Lane, Heikki Linnakangas
Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-14 23:45:36 +01:00
|
|
|
|
|
|
|
extern Datum GetAttributeByName(HeapTupleHeader tuple, const char *attname,
|
|
|
|
bool *isNull);
|
|
|
|
extern Datum GetAttributeByNum(HeapTupleHeader tuple, AttrNumber attrno,
|
|
|
|
bool *isNull);
|
|
|
|
|
|
|
|
extern int ExecTargetListLength(List *targetlist);
|
|
|
|
extern int ExecCleanTargetListLength(List *targetlist);
|
|
|
|
|
2015-04-24 08:33:23 +02:00
|
|
|
/*
|
|
|
|
* prototypes from functions in execIndexing.c
|
|
|
|
*/
|
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE.
The newly added ON CONFLICT clause allows to specify an alternative to
raising a unique or exclusion constraint violation error when inserting.
ON CONFLICT refers to constraints that can either be specified using a
inference clause (by specifying the columns of a unique constraint) or
by naming a unique or exclusion constraint. DO NOTHING avoids the
constraint violation, without touching the pre-existing row. DO UPDATE
SET ... [WHERE ...] updates the pre-existing tuple, and has access to
both the tuple proposed for insertion and the existing tuple; the
optional WHERE clause can be used to prevent an update from being
executed. The UPDATE SET and WHERE clauses have access to the tuple
proposed for insertion using the "magic" EXCLUDED alias, and to the
pre-existing tuple using the table name or its alias.
This feature is often referred to as upsert.
This is implemented using a new infrastructure called "speculative
insertion". It is an optimistic variant of regular insertion that first
does a pre-check for existing tuples and then attempts an insert. If a
violating tuple was inserted concurrently, the speculatively inserted
tuple is deleted and a new attempt is made. If the pre-check finds a
matching tuple the alternative DO NOTHING or DO UPDATE action is taken.
If the insertion succeeds without detecting a conflict, the tuple is
deemed inserted.
To handle the possible ambiguity between the excluded alias and a table
named excluded, and for convenience with long relation names, INSERT
INTO now can alias its target table.
Bumps catversion as stored rules change.
Author: Peter Geoghegan, with significant contributions from Heikki
Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes.
Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs,
Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
|
|
|
extern void ExecOpenIndices(ResultRelInfo *resultRelInfo, bool speculative);
|
2000-11-12 01:37:02 +01:00
|
|
|
extern void ExecCloseIndices(ResultRelInfo *resultRelInfo);
|
2009-07-29 22:56:21 +02:00
|
|
|
extern List *ExecInsertIndexTuples(TupleTableSlot *slot, ItemPointer tupleid,
|
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE.
The newly added ON CONFLICT clause allows to specify an alternative to
raising a unique or exclusion constraint violation error when inserting.
ON CONFLICT refers to constraints that can either be specified using a
inference clause (by specifying the columns of a unique constraint) or
by naming a unique or exclusion constraint. DO NOTHING avoids the
constraint violation, without touching the pre-existing row. DO UPDATE
SET ... [WHERE ...] updates the pre-existing tuple, and has access to
both the tuple proposed for insertion and the existing tuple; the
optional WHERE clause can be used to prevent an update from being
executed. The UPDATE SET and WHERE clauses have access to the tuple
proposed for insertion using the "magic" EXCLUDED alias, and to the
pre-existing tuple using the table name or its alias.
This feature is often referred to as upsert.
This is implemented using a new infrastructure called "speculative
insertion". It is an optimistic variant of regular insertion that first
does a pre-check for existing tuples and then attempts an insert. If a
violating tuple was inserted concurrently, the speculatively inserted
tuple is deleted and a new attempt is made. If the pre-check finds a
matching tuple the alternative DO NOTHING or DO UPDATE action is taken.
If the insertion succeeds without detecting a conflict, the tuple is
deemed inserted.
To handle the possible ambiguity between the excluded alias and a table
named excluded, and for convenience with long relation names, INSERT
INTO now can alias its target table.
Bumps catversion as stored rules change.
Author: Peter Geoghegan, with significant contributions from Heikki
Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes.
Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs,
Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
|
|
|
EState *estate, bool noDupErr, bool *specConflict,
|
|
|
|
List *arbiterIndexes);
|
|
|
|
extern bool ExecCheckIndexConstraints(TupleTableSlot *slot, EState *estate,
|
2015-05-24 03:35:49 +02:00
|
|
|
ItemPointer conflictTid, List *arbiterIndexes);
|
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE.
The newly added ON CONFLICT clause allows to specify an alternative to
raising a unique or exclusion constraint violation error when inserting.
ON CONFLICT refers to constraints that can either be specified using a
inference clause (by specifying the columns of a unique constraint) or
by naming a unique or exclusion constraint. DO NOTHING avoids the
constraint violation, without touching the pre-existing row. DO UPDATE
SET ... [WHERE ...] updates the pre-existing tuple, and has access to
both the tuple proposed for insertion and the existing tuple; the
optional WHERE clause can be used to prevent an update from being
executed. The UPDATE SET and WHERE clauses have access to the tuple
proposed for insertion using the "magic" EXCLUDED alias, and to the
pre-existing tuple using the table name or its alias.
This feature is often referred to as upsert.
This is implemented using a new infrastructure called "speculative
insertion". It is an optimistic variant of regular insertion that first
does a pre-check for existing tuples and then attempts an insert. If a
violating tuple was inserted concurrently, the speculatively inserted
tuple is deleted and a new attempt is made. If the pre-check finds a
matching tuple the alternative DO NOTHING or DO UPDATE action is taken.
If the insertion succeeds without detecting a conflict, the tuple is
deemed inserted.
To handle the possible ambiguity between the excluded alias and a table
named excluded, and for convenience with long relation names, INSERT
INTO now can alias its target table.
Bumps catversion as stored rules change.
Author: Peter Geoghegan, with significant contributions from Heikki
Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes.
Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs,
Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
|
|
|
extern void check_exclusion_constraint(Relation heap, Relation index,
|
2010-02-26 03:01:40 +01:00
|
|
|
IndexInfo *indexInfo,
|
|
|
|
ItemPointer tupleid,
|
|
|
|
Datum *values, bool *isnull,
|
Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE.
The newly added ON CONFLICT clause allows to specify an alternative to
raising a unique or exclusion constraint violation error when inserting.
ON CONFLICT refers to constraints that can either be specified using a
inference clause (by specifying the columns of a unique constraint) or
by naming a unique or exclusion constraint. DO NOTHING avoids the
constraint violation, without touching the pre-existing row. DO UPDATE
SET ... [WHERE ...] updates the pre-existing tuple, and has access to
both the tuple proposed for insertion and the existing tuple; the
optional WHERE clause can be used to prevent an update from being
executed. The UPDATE SET and WHERE clauses have access to the tuple
proposed for insertion using the "magic" EXCLUDED alias, and to the
pre-existing tuple using the table name or its alias.
This feature is often referred to as upsert.
This is implemented using a new infrastructure called "speculative
insertion". It is an optimistic variant of regular insertion that first
does a pre-check for existing tuples and then attempts an insert. If a
violating tuple was inserted concurrently, the speculatively inserted
tuple is deleted and a new attempt is made. If the pre-check finds a
matching tuple the alternative DO NOTHING or DO UPDATE action is taken.
If the insertion succeeds without detecting a conflict, the tuple is
deemed inserted.
To handle the possible ambiguity between the excluded alias and a table
named excluded, and for convenience with long relation names, INSERT
INTO now can alias its target table.
Bumps catversion as stored rules change.
Author: Peter Geoghegan, with significant contributions from Heikki
Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes.
Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs,
Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:31:36 +02:00
|
|
|
EState *estate, bool newIndex);
|
2001-10-28 07:26:15 +01:00
|
|
|
|
2017-01-19 18:00:00 +01:00
|
|
|
/*
|
|
|
|
* prototypes from functions in execReplication.c
|
|
|
|
*/
|
|
|
|
extern bool RelationFindReplTupleByIndex(Relation rel, Oid idxoid,
|
|
|
|
LockTupleMode lockmode,
|
|
|
|
TupleTableSlot *searchslot,
|
|
|
|
TupleTableSlot *outslot);
|
|
|
|
extern bool RelationFindReplTupleSeq(Relation rel, LockTupleMode lockmode,
|
|
|
|
TupleTableSlot *searchslot, TupleTableSlot *outslot);
|
|
|
|
|
|
|
|
extern void ExecSimpleRelationInsert(EState *estate, TupleTableSlot *slot);
|
|
|
|
extern void ExecSimpleRelationUpdate(EState *estate, EPQState *epqstate,
|
|
|
|
TupleTableSlot *searchslot, TupleTableSlot *slot);
|
|
|
|
extern void ExecSimpleRelationDelete(EState *estate, EPQState *epqstate,
|
|
|
|
TupleTableSlot *searchslot);
|
|
|
|
extern void CheckCmdReplicaIdentity(Relation rel, CmdType cmd);
|
|
|
|
|
2017-05-17 04:57:16 +02:00
|
|
|
extern void CheckSubscriptionRelkind(char relkind, const char *nspname,
|
2017-05-17 22:31:56 +02:00
|
|
|
const char *relname);
|
2002-05-12 22:10:05 +02:00
|
|
|
|
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 /* EXECUTOR_H */
|