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postgresql/src/include/commands/trigger.h

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CREATE/DROP TRIGGER functions
1997-08-31 13:42:21 +02:00
/*-------------------------------------------------------------------------
*
Change my-function-name-- to my_function_name, and optimizer renames.
1999-02-14 00:22:53 +01:00
* trigger.h
Second round of fmgr changes: triggers are now invoked in new style, CurrentTriggerData is history.
2000-05-29 03:59:17 +02:00
* Declarations for trigger handling.
CREATE/DROP TRIGGER functions
1997-08-31 13:42:21 +02:00
*
Stamp copyrights for year 2011.
2011-01-01 19:18:15 +01:00
* Portions Copyright (c) 1996-2011, PostgreSQL Global Development Group
Fix problems seen in parallel regress tests when SI buffer overruns (causing syscache and relcache flushes). Relcache entry rebuild now preserves original tupledesc, rewrite rules, and triggers if possible, so that pointers to these things remain valid --- if these things change while relcache entry has positive refcount, we elog(ERROR) to avoid later crash. Arrange for xact-local rels to be rebuilt when an SI inval message is seen for them, so that they are updated by CommandCounterIncrement the same as regular rels. (This is useful because of Hiroshi's recent changes to process our own SI messages at CommandCounterIncrement time.) This allows simplification of some routines that previously hacked around the lack of an automatic update. catcache now keeps its own copy of tupledesc for its relation, rather than depending on the relcache's copy; this avoids needing to reinitialize catcache during a cache flush, which saves some cycles and eliminates nasty circularity problems that occur if a cache flush happens while trying to initialize a catcache. Eliminate a number of permanent memory leaks that used to happen during catcache or relcache flush; not least of which was that catcache never freed any cached tuples! (Rule parsetree storage is still leaked, however; will fix that separately.) Nothing done yet about code that uses tuples retrieved by SearchSysCache for longer than is safe.
2000-01-31 05:35:57 +01:00
* Portions Copyright (c) 1994, Regents of the University of California
*
Remove cvs keywords from all files.
2010-09-20 22:08:53 +02:00
* src/include/commands/trigger.h
CREATE/DROP TRIGGER functions
1997-08-31 13:42:21 +02:00
*
*-------------------------------------------------------------------------
*/
#ifndef TRIGGER_H
#define TRIGGER_H
Initial MVCC code. New code for locking buffer' context.
1998-12-15 13:47:01 +01:00
#include "nodes/execnodes.h"
More cleanup
1999-07-16 19:07:40 +02:00
#include "nodes/parsenodes.h"
Function prototypes.
1997-09-01 10:10:12 +02:00
Second round of fmgr changes: triggers are now invoked in new style, CurrentTriggerData is history.
2000-05-29 03:59:17 +02:00
/*
* TriggerData is the node type that is passed as fmgr "context" info
* when a function is called by the trigger manager.
*/
#define CALLED_AS_TRIGGER(fcinfo) \
((fcinfo)->context != NULL && IsA((fcinfo)->context, TriggerData))
Another PGINDENT run that changes variable indenting and case label indenting. Also static variable indenting.
1997-09-08 04:41:22 +02:00
typedef uint32 TriggerEvent;
Function prototypes.
1997-09-01 10:10:12 +02:00
Massive commit to run PGINDENT on all *.c and *.h files.
1997-09-07 07:04:48 +02:00
typedef struct TriggerData
{
Second round of fmgr changes: triggers are now invoked in new style, CurrentTriggerData is history.
2000-05-29 03:59:17 +02:00
NodeTag type;
Another PGINDENT run that changes variable indenting and case label indenting. Also static variable indenting.
1997-09-08 04:41:22 +02:00
TriggerEvent tg_event;
Relation tg_relation;
HeapTuple tg_trigtuple;
HeapTuple tg_newtuple;
Trigger *tg_trigger;
I found a corner case in which it is possible for RI_FKey_check's call of HeapTupleSatisfiesItself() to trigger a hint-bit update on the tuple: if the row was updated or deleted by a subtransaction of my own transaction that was later rolled back. This cannot occur in pre-8.0 of course, so the hint-bit patch applied a couple weeks ago is OK for existing releases. But for 8.0 it seems we had better fix things so that RI_FKey_check can pass the correct buffer number to HeapTupleSatisfiesItself. Accordingly, add fields to the TriggerData struct to carry the buffer ID(s) for the old and new tuple(s). There are other possible solutions but this one seems cleanest; it will allow other AFTER-trigger functions to safely do tqual.c calls if they want to. Put new fields at end of struct so that there is no API breakage.
2004-10-30 22:53:06 +02:00
Buffer tg_trigtuplebuf;
Buffer tg_newtuplebuf;
pgindent run before 6.3 release, with Thomas' requested changes.
1998-02-26 05:46:47 +01:00
} TriggerData;
Function prototypes.
1997-09-01 10:10:12 +02:00
Support statement-level ON TRUNCATE triggers. Simon Riggs
2008-03-28 01:21:56 +01:00
/*
8.4 pgindent run, with new combined Linux/FreeBSD/MinGW typedef list provided by Andrew.
2009-06-11 16:49:15 +02:00
* TriggerEvent bit flags
Support statement-level ON TRUNCATE triggers. Simon Riggs
2008-03-28 01:21:56 +01:00
*
* Note that we assume different event types (INSERT/DELETE/UPDATE/TRUNCATE)
* can't be OR'd together in a single TriggerEvent. This is unlike the
* situation for pg_trigger rows, so pg_trigger.tgtype uses a different
* representation!
*/
Massive commit to run PGINDENT on all *.c and *.h files.
1997-09-07 07:04:48 +02:00
#define TRIGGER_EVENT_INSERT 0x00000000
#define TRIGGER_EVENT_DELETE 0x00000001
#define TRIGGER_EVENT_UPDATE 0x00000002
Support statement-level ON TRUNCATE triggers. Simon Riggs
2008-03-28 01:21:56 +01:00
#define TRIGGER_EVENT_TRUNCATE 0x00000003
Massive commit to run PGINDENT on all *.c and *.h files.
1997-09-07 07:04:48 +02:00
#define TRIGGER_EVENT_OPMASK 0x00000003
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
Massive commit to run PGINDENT on all *.c and *.h files.
1997-09-07 07:04:48 +02:00
#define TRIGGER_EVENT_ROW 0x00000004
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
Massive commit to run PGINDENT on all *.c and *.h files.
1997-09-07 07:04:48 +02:00
#define TRIGGER_EVENT_BEFORE 0x00000008
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
#define TRIGGER_EVENT_AFTER 0x00000000
#define TRIGGER_EVENT_INSTEAD 0x00000010
#define TRIGGER_EVENT_TIMINGMASK 0x00000018
Function prototypes.
1997-09-01 10:10:12 +02:00
Fire non-deferred AFTER triggers immediately upon query completion, rather than when returning to the idle loop. This makes no particular difference for interactively-issued queries, but it makes a big difference for queries issued within functions: trigger execution now occurs before the calling function is allowed to proceed. This responds to numerous complaints about nonintuitive behavior of foreign key checking, such as http://archives.postgresql.org/pgsql-bugs/2004-09/msg00020.php, and appears to be required by the SQL99 spec. Also take the opportunity to simplify the data structures used for the pending-trigger list, rename them for more clarity, and squeeze out a bit of space.
2004-09-10 20:40:09 +02:00
/* More TriggerEvent flags, used only within trigger.c */
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
#define AFTER_TRIGGER_DEFERRABLE 0x00000020
#define AFTER_TRIGGER_INITDEFERRED 0x00000040
This is part #1 for of the DEFERRED CONSTRAINT TRIGGER support. Implements the CREATE CONSTRAINT TRIGGER and SET CONSTRAINTS commands. TODO: Generic builtin trigger procedures Automatic execution of appropriate CREATE CONSTRAINT... at CREATE TABLE Support of new trigger type in pg_dump Swapping of huge # of events to disk Jan
1999-09-29 18:06:40 +02:00
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
#define TRIGGER_FIRED_BY_INSERT(event) \
(((event) & TRIGGER_EVENT_OPMASK) == TRIGGER_EVENT_INSERT)
Function prototypes.
1997-09-01 10:10:12 +02:00
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
#define TRIGGER_FIRED_BY_DELETE(event) \
(((event) & TRIGGER_EVENT_OPMASK) == TRIGGER_EVENT_DELETE)
Function prototypes.
1997-09-01 10:10:12 +02:00
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
#define TRIGGER_FIRED_BY_UPDATE(event) \
(((event) & TRIGGER_EVENT_OPMASK) == TRIGGER_EVENT_UPDATE)
Prototypes, definitions...
1997-09-04 15:26:19 +02:00
Support statement-level ON TRUNCATE triggers. Simon Riggs
2008-03-28 01:21:56 +01:00
#define TRIGGER_FIRED_BY_TRUNCATE(event) \
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
(((event) & TRIGGER_EVENT_OPMASK) == TRIGGER_EVENT_TRUNCATE)
#define TRIGGER_FIRED_FOR_ROW(event) \
((event) & TRIGGER_EVENT_ROW)
Support statement-level ON TRUNCATE triggers. Simon Riggs
2008-03-28 01:21:56 +01:00
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
#define TRIGGER_FIRED_FOR_STATEMENT(event) \
(!TRIGGER_FIRED_FOR_ROW(event))
Prototypes, definitions...
1997-09-04 15:26:19 +02:00
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
#define TRIGGER_FIRED_BEFORE(event) \
(((event) & TRIGGER_EVENT_TIMINGMASK) == TRIGGER_EVENT_BEFORE)
Prototypes, definitions...
1997-09-04 15:26:19 +02:00
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
#define TRIGGER_FIRED_AFTER(event) \
(((event) & TRIGGER_EVENT_TIMINGMASK) == TRIGGER_EVENT_AFTER)
Prototypes, definitions...
1997-09-04 15:26:19 +02:00
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
#define TRIGGER_FIRED_INSTEAD(event) \
(((event) & TRIGGER_EVENT_TIMINGMASK) == TRIGGER_EVENT_INSTEAD)
Function prototypes.
1997-09-01 10:10:12 +02:00
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
/*
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
* Definitions for replication role based firing.
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
*/
#define SESSION_REPLICATION_ROLE_ORIGIN 0
#define SESSION_REPLICATION_ROLE_REPLICA 1
#define SESSION_REPLICATION_ROLE_LOCAL 2
8.4 pgindent run, with new combined Linux/FreeBSD/MinGW typedef list provided by Andrew.
2009-06-11 16:49:15 +02:00
extern PGDLLIMPORT int SessionReplicationRole;
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
Update comments to reflect that tgenabled is not a boolean anymore. Jonah Harris, with minor tinkering by me.
2009-01-22 20:16:31 +01:00
/*
* States at which a trigger can be fired. These are the
* possible values for pg_trigger.tgenabled.
*/
pgindent run for 8.3.
2007-11-15 22:14:46 +01:00
#define TRIGGER_FIRES_ON_ORIGIN 'O'
#define TRIGGER_FIRES_ALWAYS 'A'
#define TRIGGER_FIRES_ON_REPLICA 'R'
#define TRIGGER_DISABLED 'D'
Function prototypes.
1997-09-01 10:10:12 +02:00
Add a WHEN clause to CREATE TRIGGER, allowing a boolean expression to be checked to determine whether the trigger should be fired. For BEFORE triggers this is mostly a matter of spec compliance; but for AFTER triggers it can provide a noticeable performance improvement, since queuing of a deferred trigger event and re-fetching of the row(s) at end of statement can be short-circuited if the trigger does not need to be fired. Takahiro Itagaki, reviewed by KaiGai Kohei.
2009-11-20 21:38:12 +01:00
extern Oid CreateTrigger(CreateTrigStmt *stmt, const char *queryString,
Improve the handling of SET CONSTRAINTS commands by having them search pg_constraint before searching pg_trigger. This allows saner handling of corner cases; in particular we now say "constraint is not deferrable" rather than "constraint does not exist" when the command is applied to a constraint that's inherently non-deferrable. Per a gripe several months ago from hubert depesz lubaczewski. To make this work without breaking user-defined constraint triggers, we have to add entries for them to pg_constraint. However, in return we can remove the pgconstrname column from pg_constraint, which represents a fairly sizable space savings. I also replaced the tgisconstraint column with tgisinternal; the old meaning of tgisconstraint can now be had by testing for nonzero tgconstraint, while there is no other way to get the old meaning of nonzero tgconstraint, namely that the trigger was internally generated rather than being user-created. In passing, fix an old misstatement in the docs and comments, namely that pg_trigger.tgdeferrable is exactly redundant with pg_constraint.condeferrable. Actually, we mark RI action triggers as nondeferrable even when they belong to a nominally deferrable FK constraint. The SET CONSTRAINTS code now relies on that instead of hard-coding a list of exception OIDs.
2010-01-17 23:56:23 +01:00
Oid constraintOid, Oid indexOid,
bool isInternal);
Second phase of committing Rod Taylor's pg_depend/pg_constraint patch. pg_relcheck is gone; CHECK, UNIQUE, PRIMARY KEY, and FOREIGN KEY constraints all have real live entries in pg_constraint. pg_depend exists, and RESTRICT/CASCADE options work on most kinds of DROP; however, pg_depend is not yet very well populated with dependencies. (Most of the ones that are present at this point just replace formerly hardwired associations, such as the implicit drop of a relation's pg_type entry when the relation is dropped.) Need to add more logic to create dependency entries, improve pg_dump to dump constraints in place of indexes and triggers, and add some regression tests.
2002-07-12 20:43:19 +02:00
extern void DropTrigger(Oid relid, const char *trigname,
DROP ... IF EXISTS for the following cases: language, tablespace, trigger, rule, opclass, function, aggregate. operator, and cast.
2006-06-16 22:23:45 +02:00
DropBehavior behavior, bool missing_ok);
Second phase of committing Rod Taylor's pg_depend/pg_constraint patch. pg_relcheck is gone; CHECK, UNIQUE, PRIMARY KEY, and FOREIGN KEY constraints all have real live entries in pg_constraint. pg_depend exists, and RESTRICT/CASCADE options work on most kinds of DROP; however, pg_depend is not yet very well populated with dependencies. (Most of the ones that are present at this point just replace formerly hardwired associations, such as the implicit drop of a relation's pg_type entry when the relation is dropped.) Need to add more logic to create dependency entries, improve pg_dump to dump constraints in place of indexes and triggers, and add some regression tests.
2002-07-12 20:43:19 +02:00
extern void RemoveTriggerById(Oid trigOid);
Standardize get_whatever_oid functions for other object types. - Rename TSParserGetPrsid to get_ts_parser_oid. - Rename TSDictionaryGetDictid to get_ts_dict_oid. - Rename TSTemplateGetTmplid to get_ts_template_oid. - Rename TSConfigGetCfgid to get_ts_config_oid. - Rename FindConversionByName to get_conversion_oid. - Rename GetConstraintName to get_constraint_oid. - Add new functions get_opclass_oid, get_opfamily_oid, get_rewrite_oid, get_rewrite_oid_without_relid, get_trigger_oid, and get_cast_oid. The name of each function matches the corresponding catalog. Thanks to KaiGai Kohei for the review.
2010-08-05 17:25:36 +02:00
extern Oid get_trigger_oid(Oid relid, const char *name, bool missing_ok);
CREATE/DROP TRIGGER functions
1997-08-31 13:42:21 +02:00
Move renametrig() from tablecmds.c to trigger.c --- if we're going to divide backend/commands by object type, let's try to pay at least minimal attention to respecting that structure, eh? Also reorder the contents of tablecmds.c; it seems odd to me to put ALTER commands before creation/deletion commands.
2002-04-26 21:29:47 +02:00
extern void renametrig(Oid relid, const char *oldname, const char *newname);
Add ALTER TABLE ENABLE/DISABLE TRIGGER commands. Change pg_dump to use these instead of its previous hack of changing pg_class.reltriggers. Documentation is lacking, will add that later. Patch by Satoshi Nagayasu, review and some extra work by Tom Lane.
2005-08-24 00:40:47 +02:00
extern void EnableDisableTrigger(Relation rel, const char *tgname,
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
char fires_when, bool skip_system);
Add ALTER TABLE ENABLE/DISABLE TRIGGER commands. Change pg_dump to use these instead of its previous hack of changing pg_class.reltriggers. Documentation is lacking, will add that later. Patch by Satoshi Nagayasu, review and some extra work by Tom Lane.
2005-08-24 00:40:47 +02:00
Fix problems seen in parallel regress tests when SI buffer overruns (causing syscache and relcache flushes). Relcache entry rebuild now preserves original tupledesc, rewrite rules, and triggers if possible, so that pointers to these things remain valid --- if these things change while relcache entry has positive refcount, we elog(ERROR) to avoid later crash. Arrange for xact-local rels to be rebuilt when an SI inval message is seen for them, so that they are updated by CommandCounterIncrement the same as regular rels. (This is useful because of Hiroshi's recent changes to process our own SI messages at CommandCounterIncrement time.) This allows simplification of some routines that previously hacked around the lack of an automatic update. catcache now keeps its own copy of tupledesc for its relation, rather than depending on the relcache's copy; this avoids needing to reinitialize catcache during a cache flush, which saves some cycles and eliminates nasty circularity problems that occur if a cache flush happens while trying to initialize a catcache. Eliminate a number of permanent memory leaks that used to happen during catcache or relcache flush; not least of which was that catcache never freed any cached tuples! (Rule parsetree storage is still leaked, however; will fix that separately.) Nothing done yet about code that uses tuples retrieved by SearchSysCache for longer than is safe.
2000-01-31 05:35:57 +01:00
extern void RelationBuildTriggers(Relation relation);
Arrange to copy relcache's trigdesc structure at the start of any query that uses it. This ensures that triggers will be applied consistently throughout a query even if someone commits changes to the relation's pg_class.reltriggers field meanwhile. Per crash report from Laurette Cisneros. While at it, simplify memory management in relcache.c, which no longer needs the old hack to try to keep trigger info in the same place over a relcache entry rebuild. (Should try to fix rd_att and rewrite-rule access similarly, someday.) And make RelationBuildTriggers simpler and more robust by making it build the trigdesc in working memory and then CopyTriggerDesc() into cache memory.
2002-10-14 18:51:30 +02:00
extern TriggerDesc *CopyTriggerDesc(TriggerDesc *trigdesc);
Fix problems seen in parallel regress tests when SI buffer overruns (causing syscache and relcache flushes). Relcache entry rebuild now preserves original tupledesc, rewrite rules, and triggers if possible, so that pointers to these things remain valid --- if these things change while relcache entry has positive refcount, we elog(ERROR) to avoid later crash. Arrange for xact-local rels to be rebuilt when an SI inval message is seen for them, so that they are updated by CommandCounterIncrement the same as regular rels. (This is useful because of Hiroshi's recent changes to process our own SI messages at CommandCounterIncrement time.) This allows simplification of some routines that previously hacked around the lack of an automatic update. catcache now keeps its own copy of tupledesc for its relation, rather than depending on the relcache's copy; this avoids needing to reinitialize catcache during a cache flush, which saves some cycles and eliminates nasty circularity problems that occur if a cache flush happens while trying to initialize a catcache. Eliminate a number of permanent memory leaks that used to happen during catcache or relcache flush; not least of which was that catcache never freed any cached tuples! (Rule parsetree storage is still leaked, however; will fix that separately.) Nothing done yet about code that uses tuples retrieved by SearchSysCache for longer than is safe.
2000-01-31 05:35:57 +01:00
Arrange to copy relcache's trigdesc structure at the start of any query that uses it. This ensures that triggers will be applied consistently throughout a query even if someone commits changes to the relation's pg_class.reltriggers field meanwhile. Per crash report from Laurette Cisneros. While at it, simplify memory management in relcache.c, which no longer needs the old hack to try to keep trigger info in the same place over a relcache entry rebuild. (Should try to fix rd_att and rewrite-rule access similarly, someday.) And make RelationBuildTriggers simpler and more robust by making it build the trigdesc in working memory and then CopyTriggerDesc() into cache memory.
2002-10-14 18:51:30 +02:00
extern void FreeTriggerDesc(TriggerDesc *trigdesc);
Fix problems seen in parallel regress tests when SI buffer overruns (causing syscache and relcache flushes). Relcache entry rebuild now preserves original tupledesc, rewrite rules, and triggers if possible, so that pointers to these things remain valid --- if these things change while relcache entry has positive refcount, we elog(ERROR) to avoid later crash. Arrange for xact-local rels to be rebuilt when an SI inval message is seen for them, so that they are updated by CommandCounterIncrement the same as regular rels. (This is useful because of Hiroshi's recent changes to process our own SI messages at CommandCounterIncrement time.) This allows simplification of some routines that previously hacked around the lack of an automatic update. catcache now keeps its own copy of tupledesc for its relation, rather than depending on the relcache's copy; this avoids needing to reinitialize catcache during a cache flush, which saves some cycles and eliminates nasty circularity problems that occur if a cache flush happens while trying to initialize a catcache. Eliminate a number of permanent memory leaks that used to happen during catcache or relcache flush; not least of which was that catcache never freed any cached tuples! (Rule parsetree storage is still leaked, however; will fix that separately.) Nothing done yet about code that uses tuples retrieved by SearchSysCache for longer than is safe.
2000-01-31 05:35:57 +01:00
This patch implements FOR EACH STATEMENT triggers, per my email to -hackers a couple days ago. Notes/caveats: - added regression tests for the new functionality, all regression tests pass on my machine - added pg_dump support - updated PL/PgSQL to support per-statement triggers; didn't look at the other procedural languages. - there's (even) more code duplication in trigger.c than there was previously. Any suggestions on how to refactor the ExecXXXTriggers() functions to reuse more code would be welcome -- I took a brief look at it, but couldn't see an easy way to do it (there are several subtly-different versions of the code in question) - updated the documentation. I also took the liberty of removing a big chunk of duplicated syntax documentation in the Programmer's Guide on triggers, and moving that information to the CREATE TRIGGER reference page. - I also included some spelling fixes and similar small cleanups I noticed while making the changes. If you'd like me to split those into a separate patch, let me know. Neil Conway
2002-11-23 04:59:09 +01:00
extern void ExecBSInsertTriggers(EState *estate,
pgindent run.
2003-08-04 02:43:34 +02:00
ResultRelInfo *relinfo);
This patch implements FOR EACH STATEMENT triggers, per my email to -hackers a couple days ago. Notes/caveats: - added regression tests for the new functionality, all regression tests pass on my machine - added pg_dump support - updated PL/PgSQL to support per-statement triggers; didn't look at the other procedural languages. - there's (even) more code duplication in trigger.c than there was previously. Any suggestions on how to refactor the ExecXXXTriggers() functions to reuse more code would be welcome -- I took a brief look at it, but couldn't see an easy way to do it (there are several subtly-different versions of the code in question) - updated the documentation. I also took the liberty of removing a big chunk of duplicated syntax documentation in the Programmer's Guide on triggers, and moving that information to the CREATE TRIGGER reference page. - I also included some spelling fixes and similar small cleanups I noticed while making the changes. If you'd like me to split those into a separate patch, let me know. Neil Conway
2002-11-23 04:59:09 +01:00
extern void ExecASInsertTriggers(EState *estate,
pgindent run.
2003-08-04 02:43:34 +02:00
ResultRelInfo *relinfo);
Fix dangling-pointer problem in before-row update trigger processing. ExecUpdate checked for whether ExecBRUpdateTriggers had returned a new tuple value by seeing if the returned tuple was pointer-equal to the old one. But the "old one" was in estate->es_junkFilter's result slot, which would be scribbled on if we had done an EvalPlanQual update in response to a concurrent update of the target tuple; therefore we were comparing a dangling pointer to a live one. Given the right set of circumstances we could get a false match, resulting in not forcing the tuple to be stored in the slot we thought it was stored in. In the case reported by Maxim Boguk in bug #5798, this led to "cannot extract system attribute from virtual tuple" failures when trying to do "RETURNING ctid". I believe there is a very-low-probability chance of more serious errors, such as generating incorrect index entries based on the original rather than the trigger-modified version of the row. In HEAD, change all of ExecBRInsertTriggers, ExecIRInsertTriggers, ExecBRUpdateTriggers, and ExecIRUpdateTriggers so that they continue to have similar APIs. In the back branches I just changed ExecBRUpdateTriggers, since there is no bug in the ExecBRInsertTriggers case.
2011-02-22 03:18:04 +01:00
extern TupleTableSlot *ExecBRInsertTriggers(EState *estate,
pgindent run on all C files. Java run to follow. initdb/regression tests pass.
2001-10-25 07:50:21 +02:00
ResultRelInfo *relinfo,
Fix dangling-pointer problem in before-row update trigger processing. ExecUpdate checked for whether ExecBRUpdateTriggers had returned a new tuple value by seeing if the returned tuple was pointer-equal to the old one. But the "old one" was in estate->es_junkFilter's result slot, which would be scribbled on if we had done an EvalPlanQual update in response to a concurrent update of the target tuple; therefore we were comparing a dangling pointer to a live one. Given the right set of circumstances we could get a false match, resulting in not forcing the tuple to be stored in the slot we thought it was stored in. In the case reported by Maxim Boguk in bug #5798, this led to "cannot extract system attribute from virtual tuple" failures when trying to do "RETURNING ctid". I believe there is a very-low-probability chance of more serious errors, such as generating incorrect index entries based on the original rather than the trigger-modified version of the row. In HEAD, change all of ExecBRInsertTriggers, ExecIRInsertTriggers, ExecBRUpdateTriggers, and ExecIRUpdateTriggers so that they continue to have similar APIs. In the back branches I just changed ExecBRUpdateTriggers, since there is no bug in the ExecBRInsertTriggers case.
2011-02-22 03:18:04 +01:00
TupleTableSlot *slot);
Clean up per-tuple memory leaks in trigger firing and plpgsql expression evaluation.
2001-01-22 01:50:07 +01:00
extern void ExecARInsertTriggers(EState *estate,
pgindent run on all C files. Java run to follow. initdb/regression tests pass.
2001-10-25 07:50:21 +02:00
ResultRelInfo *relinfo,
Support deferrable uniqueness constraints. The current implementation fires an AFTER ROW trigger for each tuple that looks like it might be non-unique according to the index contents at the time of insertion. This works well as long as there aren't many conflicts, but won't scale to massive unique-key reassignments. Improving that case is a TODO item. Dean Rasheed
2009-07-29 22:56:21 +02:00
HeapTuple trigtuple,
List *recheckIndexes);
Fix dangling-pointer problem in before-row update trigger processing. ExecUpdate checked for whether ExecBRUpdateTriggers had returned a new tuple value by seeing if the returned tuple was pointer-equal to the old one. But the "old one" was in estate->es_junkFilter's result slot, which would be scribbled on if we had done an EvalPlanQual update in response to a concurrent update of the target tuple; therefore we were comparing a dangling pointer to a live one. Given the right set of circumstances we could get a false match, resulting in not forcing the tuple to be stored in the slot we thought it was stored in. In the case reported by Maxim Boguk in bug #5798, this led to "cannot extract system attribute from virtual tuple" failures when trying to do "RETURNING ctid". I believe there is a very-low-probability chance of more serious errors, such as generating incorrect index entries based on the original rather than the trigger-modified version of the row. In HEAD, change all of ExecBRInsertTriggers, ExecIRInsertTriggers, ExecBRUpdateTriggers, and ExecIRUpdateTriggers so that they continue to have similar APIs. In the back branches I just changed ExecBRUpdateTriggers, since there is no bug in the ExecBRInsertTriggers case.
2011-02-22 03:18:04 +01:00
extern TupleTableSlot *ExecIRInsertTriggers(EState *estate,
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
ResultRelInfo *relinfo,
Fix dangling-pointer problem in before-row update trigger processing. ExecUpdate checked for whether ExecBRUpdateTriggers had returned a new tuple value by seeing if the returned tuple was pointer-equal to the old one. But the "old one" was in estate->es_junkFilter's result slot, which would be scribbled on if we had done an EvalPlanQual update in response to a concurrent update of the target tuple; therefore we were comparing a dangling pointer to a live one. Given the right set of circumstances we could get a false match, resulting in not forcing the tuple to be stored in the slot we thought it was stored in. In the case reported by Maxim Boguk in bug #5798, this led to "cannot extract system attribute from virtual tuple" failures when trying to do "RETURNING ctid". I believe there is a very-low-probability chance of more serious errors, such as generating incorrect index entries based on the original rather than the trigger-modified version of the row. In HEAD, change all of ExecBRInsertTriggers, ExecIRInsertTriggers, ExecBRUpdateTriggers, and ExecIRUpdateTriggers so that they continue to have similar APIs. In the back branches I just changed ExecBRUpdateTriggers, since there is no bug in the ExecBRInsertTriggers case.
2011-02-22 03:18:04 +01:00
TupleTableSlot *slot);
This patch implements FOR EACH STATEMENT triggers, per my email to -hackers a couple days ago. Notes/caveats: - added regression tests for the new functionality, all regression tests pass on my machine - added pg_dump support - updated PL/PgSQL to support per-statement triggers; didn't look at the other procedural languages. - there's (even) more code duplication in trigger.c than there was previously. Any suggestions on how to refactor the ExecXXXTriggers() functions to reuse more code would be welcome -- I took a brief look at it, but couldn't see an easy way to do it (there are several subtly-different versions of the code in question) - updated the documentation. I also took the liberty of removing a big chunk of duplicated syntax documentation in the Programmer's Guide on triggers, and moving that information to the CREATE TRIGGER reference page. - I also included some spelling fixes and similar small cleanups I noticed while making the changes. If you'd like me to split those into a separate patch, let me know. Neil Conway
2002-11-23 04:59:09 +01:00
extern void ExecBSDeleteTriggers(EState *estate,
pgindent run.
2003-08-04 02:43:34 +02:00
ResultRelInfo *relinfo);
This patch implements FOR EACH STATEMENT triggers, per my email to -hackers a couple days ago. Notes/caveats: - added regression tests for the new functionality, all regression tests pass on my machine - added pg_dump support - updated PL/PgSQL to support per-statement triggers; didn't look at the other procedural languages. - there's (even) more code duplication in trigger.c than there was previously. Any suggestions on how to refactor the ExecXXXTriggers() functions to reuse more code would be welcome -- I took a brief look at it, but couldn't see an easy way to do it (there are several subtly-different versions of the code in question) - updated the documentation. I also took the liberty of removing a big chunk of duplicated syntax documentation in the Programmer's Guide on triggers, and moving that information to the CREATE TRIGGER reference page. - I also included some spelling fixes and similar small cleanups I noticed while making the changes. If you'd like me to split those into a separate patch, let me know. Neil Conway
2002-11-23 04:59:09 +01:00
extern void ExecASDeleteTriggers(EState *estate,
pgindent run.
2003-08-04 02:43:34 +02:00
ResultRelInfo *relinfo);
Clean up some minor problems exposed by further thought about Panon's bug report on old-style functions invoked by RI triggers. We had a number of other places that were being sloppy about which memory context FmgrInfo subsidiary data will be allocated in. Turns out none of them actually cause a problem in 7.1, but this is for arcane reasons such as the fact that old-style triggers aren't supported anyway. To avoid getting burnt later, I've restructured the trigger support so that we don't keep trigger FmgrInfo structs in relcache memory. Some other related cleanups too: it's not really necessary to call fmgr_info at all while setting up the index support info in relcache entries, because those ScanKeyEntry structs are never used to invoke the functions. This should speed up relcache initialization a tiny bit.
2001-06-01 04:41:36 +02:00
extern bool ExecBRDeleteTriggers(EState *estate,
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
EPQState *epqstate,
pgindent run.
2003-08-04 02:43:34 +02:00
ResultRelInfo *relinfo,
Avoid incrementing the CommandCounter when CommandCounterIncrement is called but no database changes have been made since the last CommandCounterIncrement. This should result in a significant improvement in the number of "commands" that can typically be performed within a transaction before hitting the 2^32 CommandId size limit. In particular this buys back (and more) the possible adverse consequences of my previous patch to fix plan caching behavior. The implementation requires tracking whether the current CommandCounter value has been "used" to mark any tuples. CommandCounter values stored into snapshots are presumed not to be used for this purpose. This requires some small executor changes, since the executor used to conflate the curcid of the snapshot it was using with the command ID to mark output tuples with. Separating these concepts allows some small simplifications in executor APIs. Something for the TODO list: look into having CommandCounterIncrement not do AcceptInvalidationMessages. It seems fairly bogus to be doing it there, but exactly where to do it instead isn't clear, and I'm disinclined to mess with asynchronous behavior during late beta.
2007-11-30 22:22:54 +01:00
ItemPointer tupleid);
Clean up some minor problems exposed by further thought about Panon's bug report on old-style functions invoked by RI triggers. We had a number of other places that were being sloppy about which memory context FmgrInfo subsidiary data will be allocated in. Turns out none of them actually cause a problem in 7.1, but this is for arcane reasons such as the fact that old-style triggers aren't supported anyway. To avoid getting burnt later, I've restructured the trigger support so that we don't keep trigger FmgrInfo structs in relcache memory. Some other related cleanups too: it's not really necessary to call fmgr_info at all while setting up the index support info in relcache entries, because those ScanKeyEntry structs are never used to invoke the functions. This should speed up relcache initialization a tiny bit.
2001-06-01 04:41:36 +02:00
extern void ExecARDeleteTriggers(EState *estate,
pgindent run on all C files. Java run to follow. initdb/regression tests pass.
2001-10-25 07:50:21 +02:00
ResultRelInfo *relinfo,
ItemPointer tupleid);
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
extern bool ExecIRDeleteTriggers(EState *estate,
ResultRelInfo *relinfo,
HeapTuple trigtuple);
This patch implements FOR EACH STATEMENT triggers, per my email to -hackers a couple days ago. Notes/caveats: - added regression tests for the new functionality, all regression tests pass on my machine - added pg_dump support - updated PL/PgSQL to support per-statement triggers; didn't look at the other procedural languages. - there's (even) more code duplication in trigger.c than there was previously. Any suggestions on how to refactor the ExecXXXTriggers() functions to reuse more code would be welcome -- I took a brief look at it, but couldn't see an easy way to do it (there are several subtly-different versions of the code in question) - updated the documentation. I also took the liberty of removing a big chunk of duplicated syntax documentation in the Programmer's Guide on triggers, and moving that information to the CREATE TRIGGER reference page. - I also included some spelling fixes and similar small cleanups I noticed while making the changes. If you'd like me to split those into a separate patch, let me know. Neil Conway
2002-11-23 04:59:09 +01:00
extern void ExecBSUpdateTriggers(EState *estate,
pgindent run.
2003-08-04 02:43:34 +02:00
ResultRelInfo *relinfo);
This patch implements FOR EACH STATEMENT triggers, per my email to -hackers a couple days ago. Notes/caveats: - added regression tests for the new functionality, all regression tests pass on my machine - added pg_dump support - updated PL/PgSQL to support per-statement triggers; didn't look at the other procedural languages. - there's (even) more code duplication in trigger.c than there was previously. Any suggestions on how to refactor the ExecXXXTriggers() functions to reuse more code would be welcome -- I took a brief look at it, but couldn't see an easy way to do it (there are several subtly-different versions of the code in question) - updated the documentation. I also took the liberty of removing a big chunk of duplicated syntax documentation in the Programmer's Guide on triggers, and moving that information to the CREATE TRIGGER reference page. - I also included some spelling fixes and similar small cleanups I noticed while making the changes. If you'd like me to split those into a separate patch, let me know. Neil Conway
2002-11-23 04:59:09 +01:00
extern void ExecASUpdateTriggers(EState *estate,
pgindent run.
2003-08-04 02:43:34 +02:00
ResultRelInfo *relinfo);
Fix dangling-pointer problem in before-row update trigger processing. ExecUpdate checked for whether ExecBRUpdateTriggers had returned a new tuple value by seeing if the returned tuple was pointer-equal to the old one. But the "old one" was in estate->es_junkFilter's result slot, which would be scribbled on if we had done an EvalPlanQual update in response to a concurrent update of the target tuple; therefore we were comparing a dangling pointer to a live one. Given the right set of circumstances we could get a false match, resulting in not forcing the tuple to be stored in the slot we thought it was stored in. In the case reported by Maxim Boguk in bug #5798, this led to "cannot extract system attribute from virtual tuple" failures when trying to do "RETURNING ctid". I believe there is a very-low-probability chance of more serious errors, such as generating incorrect index entries based on the original rather than the trigger-modified version of the row. In HEAD, change all of ExecBRInsertTriggers, ExecIRInsertTriggers, ExecBRUpdateTriggers, and ExecIRUpdateTriggers so that they continue to have similar APIs. In the back branches I just changed ExecBRUpdateTriggers, since there is no bug in the ExecBRInsertTriggers case.
2011-02-22 03:18:04 +01:00
extern TupleTableSlot *ExecBRUpdateTriggers(EState *estate,
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
EPQState *epqstate,
pgindent run.
2003-08-04 02:43:34 +02:00
ResultRelInfo *relinfo,
ItemPointer tupleid,
Fix dangling-pointer problem in before-row update trigger processing. ExecUpdate checked for whether ExecBRUpdateTriggers had returned a new tuple value by seeing if the returned tuple was pointer-equal to the old one. But the "old one" was in estate->es_junkFilter's result slot, which would be scribbled on if we had done an EvalPlanQual update in response to a concurrent update of the target tuple; therefore we were comparing a dangling pointer to a live one. Given the right set of circumstances we could get a false match, resulting in not forcing the tuple to be stored in the slot we thought it was stored in. In the case reported by Maxim Boguk in bug #5798, this led to "cannot extract system attribute from virtual tuple" failures when trying to do "RETURNING ctid". I believe there is a very-low-probability chance of more serious errors, such as generating incorrect index entries based on the original rather than the trigger-modified version of the row. In HEAD, change all of ExecBRInsertTriggers, ExecIRInsertTriggers, ExecBRUpdateTriggers, and ExecIRUpdateTriggers so that they continue to have similar APIs. In the back branches I just changed ExecBRUpdateTriggers, since there is no bug in the ExecBRInsertTriggers case.
2011-02-22 03:18:04 +01:00
TupleTableSlot *slot);
Clean up some minor problems exposed by further thought about Panon's bug report on old-style functions invoked by RI triggers. We had a number of other places that were being sloppy about which memory context FmgrInfo subsidiary data will be allocated in. Turns out none of them actually cause a problem in 7.1, but this is for arcane reasons such as the fact that old-style triggers aren't supported anyway. To avoid getting burnt later, I've restructured the trigger support so that we don't keep trigger FmgrInfo structs in relcache memory. Some other related cleanups too: it's not really necessary to call fmgr_info at all while setting up the index support info in relcache entries, because those ScanKeyEntry structs are never used to invoke the functions. This should speed up relcache initialization a tiny bit.
2001-06-01 04:41:36 +02:00
extern void ExecARUpdateTriggers(EState *estate,
pgindent run on all C files. Java run to follow. initdb/regression tests pass.
2001-10-25 07:50:21 +02:00
ResultRelInfo *relinfo,
ItemPointer tupleid,
Support deferrable uniqueness constraints. The current implementation fires an AFTER ROW trigger for each tuple that looks like it might be non-unique according to the index contents at the time of insertion. This works well as long as there aren't many conflicts, but won't scale to massive unique-key reassignments. Improving that case is a TODO item. Dean Rasheed
2009-07-29 22:56:21 +02:00
HeapTuple newtuple,
List *recheckIndexes);
Fix dangling-pointer problem in before-row update trigger processing. ExecUpdate checked for whether ExecBRUpdateTriggers had returned a new tuple value by seeing if the returned tuple was pointer-equal to the old one. But the "old one" was in estate->es_junkFilter's result slot, which would be scribbled on if we had done an EvalPlanQual update in response to a concurrent update of the target tuple; therefore we were comparing a dangling pointer to a live one. Given the right set of circumstances we could get a false match, resulting in not forcing the tuple to be stored in the slot we thought it was stored in. In the case reported by Maxim Boguk in bug #5798, this led to "cannot extract system attribute from virtual tuple" failures when trying to do "RETURNING ctid". I believe there is a very-low-probability chance of more serious errors, such as generating incorrect index entries based on the original rather than the trigger-modified version of the row. In HEAD, change all of ExecBRInsertTriggers, ExecIRInsertTriggers, ExecBRUpdateTriggers, and ExecIRUpdateTriggers so that they continue to have similar APIs. In the back branches I just changed ExecBRUpdateTriggers, since there is no bug in the ExecBRInsertTriggers case.
2011-02-22 03:18:04 +01:00
extern TupleTableSlot *ExecIRUpdateTriggers(EState *estate,
Support triggers on views. This patch adds the SQL-standard concept of an INSTEAD OF trigger, which is fired instead of performing a physical insert/update/delete. The trigger function is passed the entire old and/or new rows of the view, and must figure out what to do to the underlying tables to implement the update. So this feature can be used to implement updatable views using trigger programming style rather than rule hacking. In passing, this patch corrects the names of some columns in the information_schema.triggers view. It seems the SQL committee renamed them somewhere between SQL:99 and SQL:2003. Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.
2010-10-10 19:43:33 +02:00
ResultRelInfo *relinfo,
Fix dangling-pointer problem in before-row update trigger processing. ExecUpdate checked for whether ExecBRUpdateTriggers had returned a new tuple value by seeing if the returned tuple was pointer-equal to the old one. But the "old one" was in estate->es_junkFilter's result slot, which would be scribbled on if we had done an EvalPlanQual update in response to a concurrent update of the target tuple; therefore we were comparing a dangling pointer to a live one. Given the right set of circumstances we could get a false match, resulting in not forcing the tuple to be stored in the slot we thought it was stored in. In the case reported by Maxim Boguk in bug #5798, this led to "cannot extract system attribute from virtual tuple" failures when trying to do "RETURNING ctid". I believe there is a very-low-probability chance of more serious errors, such as generating incorrect index entries based on the original rather than the trigger-modified version of the row. In HEAD, change all of ExecBRInsertTriggers, ExecIRInsertTriggers, ExecBRUpdateTriggers, and ExecIRUpdateTriggers so that they continue to have similar APIs. In the back branches I just changed ExecBRUpdateTriggers, since there is no bug in the ExecBRInsertTriggers case.
2011-02-22 03:18:04 +01:00
HeapTuple trigtuple,
TupleTableSlot *slot);
Support statement-level ON TRUNCATE triggers. Simon Riggs
2008-03-28 01:21:56 +01:00
extern void ExecBSTruncateTriggers(EState *estate,
8.4 pgindent run, with new combined Linux/FreeBSD/MinGW typedef list provided by Andrew.
2009-06-11 16:49:15 +02:00
ResultRelInfo *relinfo);
Support statement-level ON TRUNCATE triggers. Simon Riggs
2008-03-28 01:21:56 +01:00
extern void ExecASTruncateTriggers(EState *estate,
8.4 pgindent run, with new combined Linux/FreeBSD/MinGW typedef list provided by Andrew.
2009-06-11 16:49:15 +02:00
ResultRelInfo *relinfo);
This is part #1 for of the DEFERRED CONSTRAINT TRIGGER support. Implements the CREATE CONSTRAINT TRIGGER and SET CONSTRAINTS commands. TODO: Generic builtin trigger procedures Automatic execution of appropriate CREATE CONSTRAINT... at CREATE TABLE Support of new trigger type in pg_dump Swapping of huge # of events to disk Jan
1999-09-29 18:06:40 +02:00
Fire non-deferred AFTER triggers immediately upon query completion, rather than when returning to the idle loop. This makes no particular difference for interactively-issued queries, but it makes a big difference for queries issued within functions: trigger execution now occurs before the calling function is allowed to proceed. This responds to numerous complaints about nonintuitive behavior of foreign key checking, such as http://archives.postgresql.org/pgsql-bugs/2004-09/msg00020.php, and appears to be required by the SQL99 spec. Also take the opportunity to simplify the data structures used for the pending-trigger list, rename them for more clarity, and squeeze out a bit of space.
2004-09-10 20:40:09 +02:00
extern void AfterTriggerBeginXact(void);
extern void AfterTriggerBeginQuery(void);
Improve EXPLAIN ANALYZE to show the time spent in each trigger when executing a statement that fires triggers. Formerly this time was included in "Total runtime" but not otherwise accounted for. As a side benefit, we avoid re-opening relations when firing non-deferred AFTER triggers, because the trigger code can re-use the main executor's ResultRelInfo data structure.
2005-03-25 22:58:00 +01:00
extern void AfterTriggerEndQuery(EState *estate);
Fix interaction between materializing holdable cursors and firing deferred triggers: either one can create more work for the other, so we have to loop till it's all gone. Per example from andrew@supernews. Add a regression test to help spot trouble in this area in future.
2005-04-11 21:51:16 +02:00
extern void AfterTriggerFireDeferred(void);
extern void AfterTriggerEndXact(bool isCommit);
Fire non-deferred AFTER triggers immediately upon query completion, rather than when returning to the idle loop. This makes no particular difference for interactively-issued queries, but it makes a big difference for queries issued within functions: trigger execution now occurs before the calling function is allowed to proceed. This responds to numerous complaints about nonintuitive behavior of foreign key checking, such as http://archives.postgresql.org/pgsql-bugs/2004-09/msg00020.php, and appears to be required by the SQL99 spec. Also take the opportunity to simplify the data structures used for the pending-trigger list, rename them for more clarity, and squeeze out a bit of space.
2004-09-10 20:40:09 +02:00
extern void AfterTriggerBeginSubXact(void);
extern void AfterTriggerEndSubXact(bool isCommit);
extern void AfterTriggerSetState(ConstraintsSetStmt *stmt);
Forbid ALTER TABLE and CLUSTER when there are pending AFTER-trigger events in the current backend for the target table. These operations move tuples around and would thus invalidate the TIDs stored in the trigger event records. (We need not worry about events in other backends, since acquiring exclusive lock should be enough to ensure there aren't any.) It might be sufficient to forbid only the table-rewriting variants of ALTER TABLE, but in the absence of any compelling use-case, let's just be safe and simple. Per follow-on investigation of bug #3847, though this is not actually the same problem reported therein. Possibly this should be back-patched, but since the case has never been reported from the field, I didn't bother.
2008-01-03 00:34:42 +01:00
extern bool AfterTriggerPendingOnRel(Oid relid);
This is part #1 for of the DEFERRED CONSTRAINT TRIGGER support. Implements the CREATE CONSTRAINT TRIGGER and SET CONSTRAINTS commands. TODO: Generic builtin trigger procedures Automatic execution of appropriate CREATE CONSTRAINT... at CREATE TABLE Support of new trigger type in pg_dump Swapping of huge # of events to disk Jan
1999-09-29 18:06:40 +02:00
Changed "triggered data change violation" detection code in trigger manager. Jan
2000-01-06 21:47:01 +01:00
/*
* in utils/adt/ri_triggers.c
*/
When enqueueing after-row triggers for updates of a table with a foreign key, compare the new and old row versions. If the foreign key column has not changed, we needn't enqueue the trigger, since the update cannot violate the foreign key. This optimization was previously applied in the RI trigger function, but it is more efficient to avoid firing the trigger altogether. Per recent discussion on pgsql-hackers. Also add a regression test for some unintuitive foreign key behavior, and refactor some code that deals with the OIDs of the various RI trigger functions.
2005-05-30 09:20:59 +02:00
extern bool RI_FKey_keyequal_upd_pk(Trigger *trigger, Relation pk_rel,
Standard pgindent run for 8.1.
2005-10-15 04:49:52 +02:00
HeapTuple old_row, HeapTuple new_row);
When enqueueing after-row triggers for updates of a table with a foreign key, compare the new and old row versions. If the foreign key column has not changed, we needn't enqueue the trigger, since the update cannot violate the foreign key. This optimization was previously applied in the RI trigger function, but it is more efficient to avoid firing the trigger altogether. Per recent discussion on pgsql-hackers. Also add a regression test for some unintuitive foreign key behavior, and refactor some code that deals with the OIDs of the various RI trigger functions.
2005-05-30 09:20:59 +02:00
extern bool RI_FKey_keyequal_upd_fk(Trigger *trigger, Relation fk_rel,
Standard pgindent run for 8.1.
2005-10-15 04:49:52 +02:00
HeapTuple old_row, HeapTuple new_row);
Fix up foreign-key mechanism so that there is a sound semantic basis for the equality checks it applies, instead of a random dependence on whatever operators might be named "=". The equality operators will now be selected from the opfamily of the unique index that the FK constraint depends on to enforce uniqueness of the referenced columns; therefore they are certain to be consistent with that index's notion of equality. Among other things this should fix the problem noted awhile back that pg_dump may fail for foreign-key constraints on user-defined types when the required operators aren't in the search path. This also means that the former warning condition about "foreign key constraint will require costly sequential scans" is gone: if the comparison condition isn't indexable then we'll reject the constraint entirely. All per past discussions. Along the way, make the RI triggers look into pg_constraint for their information, instead of using pg_trigger.tgargs; and get rid of the always error-prone fixed-size string buffers in ri_triggers.c in favor of building up the RI queries in StringInfo buffers. initdb forced due to columns added to pg_constraint and pg_trigger.
2007-02-14 02:58:58 +01:00
extern bool RI_Initial_Check(Trigger *trigger,
pgindent run for 8.3.
2007-11-15 22:14:46 +01:00
Relation fk_rel, Relation pk_rel);
Another pgindent run. Fixes enum indenting, and improves #endif spacing. Also adds space for one-line comments.
2001-10-28 07:26:15 +01:00
Fix up foreign-key mechanism so that there is a sound semantic basis for the equality checks it applies, instead of a random dependence on whatever operators might be named "=". The equality operators will now be selected from the opfamily of the unique index that the FK constraint depends on to enforce uniqueness of the referenced columns; therefore they are certain to be consistent with that index's notion of equality. Among other things this should fix the problem noted awhile back that pg_dump may fail for foreign-key constraints on user-defined types when the required operators aren't in the search path. This also means that the former warning condition about "foreign key constraint will require costly sequential scans" is gone: if the comparison condition isn't indexable then we'll reject the constraint entirely. All per past discussions. Along the way, make the RI triggers look into pg_constraint for their information, instead of using pg_trigger.tgargs; and get rid of the always error-prone fixed-size string buffers in ri_triggers.c in favor of building up the RI queries in StringInfo buffers. initdb forced due to columns added to pg_constraint and pg_trigger.
2007-02-14 02:58:58 +01:00
/* result values for RI_FKey_trigger_type: */
When enqueueing after-row triggers for updates of a table with a foreign key, compare the new and old row versions. If the foreign key column has not changed, we needn't enqueue the trigger, since the update cannot violate the foreign key. This optimization was previously applied in the RI trigger function, but it is more efficient to avoid firing the trigger altogether. Per recent discussion on pgsql-hackers. Also add a regression test for some unintuitive foreign key behavior, and refactor some code that deals with the OIDs of the various RI trigger functions.
2005-05-30 09:20:59 +02:00
#define RI_TRIGGER_PK 1 /* is a trigger on the PK relation */
#define RI_TRIGGER_FK 2 /* is a trigger on the FK relation */
#define RI_TRIGGER_NONE 0 /* is not an RI trigger function */
Standard pgindent run for 8.1.
2005-10-15 04:49:52 +02:00
extern int RI_FKey_trigger_type(Oid tgfoid);
When enqueueing after-row triggers for updates of a table with a foreign key, compare the new and old row versions. If the foreign key column has not changed, we needn't enqueue the trigger, since the update cannot violate the foreign key. This optimization was previously applied in the RI trigger function, but it is more efficient to avoid firing the trigger altogether. Per recent discussion on pgsql-hackers. Also add a regression test for some unintuitive foreign key behavior, and refactor some code that deals with the OIDs of the various RI trigger functions.
2005-05-30 09:20:59 +02:00
New pgindent run with fixes suggested by Tom. Patch manually reviewed, initdb/regression tests pass.
2001-11-05 18:46:40 +01:00
#endif /* TRIGGER_H */