greenplumn trigger 源码
greenplumn trigger 代码
文件路径：/src/backend/commands/trigger.c
/*-------------------------------------------------------------------------
*
* trigger.c
* PostgreSQL TRIGGERs support code.
*
* Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* src/backend/commands/trigger.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/genam.h"
#include "access/htup_details.h"
#include "access/relation.h"
#include "access/sysattr.h"
#include "access/table.h"
#include "access/tableam.h"
#include "access/xact.h"
#include "catalog/catalog.h"
#include "catalog/dependency.h"
#include "catalog/index.h"
#include "catalog/indexing.h"
#include "catalog/objectaccess.h"
#include "catalog/partition.h"
#include "catalog/pg_constraint.h"
#include "catalog/pg_inherits.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_trigger.h"
#include "catalog/pg_type.h"
#include "commands/dbcommands.h"
#include "commands/defrem.h"
#include "commands/trigger.h"
#include "executor/executor.h"
#include "miscadmin.h"
#include "nodes/execnodes.h"
#include "nodes/bitmapset.h"
#include "nodes/makefuncs.h"
#include "optimizer/optimizer.h"
#include "parser/parse_clause.h"
#include "parser/parse_collate.h"
#include "parser/parse_func.h"
#include "parser/parse_relation.h"
#include "parser/parsetree.h"
#include "partitioning/partdesc.h"
#include "pgstat.h"
#include "rewrite/rewriteManip.h"
#include "storage/bufmgr.h"
#include "storage/lmgr.h"
#include "tcop/utility.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/bytea.h"
#include "utils/fmgroids.h"
#include "utils/inval.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/rel.h"
#include "utils/snapmgr.h"
#include "utils/syscache.h"
#include "utils/tuplestore.h"
#include "catalog/oid_dispatch.h"
#include "cdb/cdbvars.h"
#include "cdb/cdbdisp_query.h"
/* GUC variables */
int SessionReplicationRole = SESSION_REPLICATION_ROLE_ORIGIN;
/* How many levels deep into trigger execution are we? */
static int MyTriggerDepth = 0;
/*
* Note that similar macros also exist in executor/execMain.c. There does not
* appear to be any good header to put them into, given the structures that
* they use, so we let them be duplicated. Be sure to update all if one needs
* to be changed, however.
*/
#define GetAllUpdatedColumns(relinfo, estate) \
(bms_union(exec_rt_fetch((relinfo)->ri_RangeTableIndex, estate)->updatedCols, \
exec_rt_fetch((relinfo)->ri_RangeTableIndex, estate)->extraUpdatedCols))
/* Local function prototypes */
static void ConvertTriggerToFK(CreateTrigStmt *stmt, Oid funcoid);
static void SetTriggerFlags(TriggerDesc *trigdesc, Trigger *trigger);
static bool GetTupleForTrigger(EState *estate,
EPQState *epqstate,
ResultRelInfo *relinfo,
ItemPointer tid,
LockTupleMode lockmode,
TupleTableSlot *oldslot,
TupleTableSlot **newSlot);
static bool TriggerEnabled(EState *estate, ResultRelInfo *relinfo,
Trigger *trigger, TriggerEvent event,
Bitmapset *modifiedCols,
TupleTableSlot *oldslot, TupleTableSlot *newslot);
static HeapTuple ExecCallTriggerFunc(TriggerData *trigdata,
int tgindx,
FmgrInfo *finfo,
Instrumentation *instr,
MemoryContext per_tuple_context);
static void AfterTriggerSaveEvent(EState *estate, ResultRelInfo *relinfo,
int event, bool row_trigger,
TupleTableSlot *oldtup, TupleTableSlot *newtup,
List *recheckIndexes, Bitmapset *modifiedCols,
TransitionCaptureState *transition_capture);
static void AfterTriggerEnlargeQueryState(void);
static bool before_stmt_triggers_fired(Oid relid, CmdType cmdType);
/*
* Create a trigger. Returns the address of the created trigger.
*
* queryString is the source text of the CREATE TRIGGER command.
* This must be supplied if a whenClause is specified, else it can be NULL.
*
* relOid, if nonzero, is the relation on which the trigger should be
* created. If zero, the name provided in the statement will be looked up.
*
* refRelOid, if nonzero, is the relation to which the constraint trigger
* refers. If zero, the constraint relation name provided in the statement
* will be looked up as needed.
*
* constraintOid, if nonzero, says that this trigger is being created
* internally to implement that constraint. A suitable pg_depend entry will
* be made to link the trigger to that constraint. constraintOid is zero when
* executing a user-entered CREATE TRIGGER command. (For CREATE CONSTRAINT
* TRIGGER, we build a pg_constraint entry internally.)
*
* indexOid, if nonzero, is the OID of an index associated with the constraint.
* We do nothing with this except store it into pg_trigger.tgconstrindid;
* but when creating a trigger for a deferrable unique constraint on a
* partitioned table, its children are looked up. Note we don't cope with
* invalid indexes in that case.
*
* funcoid, if nonzero, is the OID of the function to invoke. When this is
* given, stmt->funcname is ignored.
*
* parentTriggerOid, if nonzero, is a trigger that begets this one; so that
* if that trigger is dropped, this one should be too. (This is passed as
* Invalid by most callers; it's set here when recursing on a partition.)
*
* If whenClause is passed, it is an already-transformed expression for
* WHEN. In this case, we ignore any that may come in stmt->whenClause.
*
* If isInternal is true then this is an internally-generated trigger.
* This argument sets the tgisinternal field of the pg_trigger entry, and
* if true causes us to modify the given trigger name to ensure uniqueness.
*
* When isInternal is not true we require ACL_TRIGGER permissions on the
* relation, as well as ACL_EXECUTE on the trigger function. For internal
* triggers the caller must apply any required permission checks.
*
* When called on partitioned tables, this function recurses to create the
* trigger on all the partitions, except if isInternal is true, in which
* case caller is expected to execute recursion on its own.
*
* Note: can return InvalidObjectAddress if we decided to not create a trigger
* at all, but a foreign-key constraint. This is a kluge for backwards
* compatibility.
*/
ObjectAddress
CreateTrigger(CreateTrigStmt *stmt, const char *queryString,
Oid relOid, Oid refRelOid, Oid constraintOid, Oid indexOid,
Oid funcoid, Oid parentTriggerOid, Node *whenClause,
bool isInternal, bool in_partition)
{
int16 tgtype;
int ncolumns;
int16 *columns;
int2vector *tgattr;
List *whenRtable;
char *qual;
Datum values[Natts_pg_trigger];
bool nulls[Natts_pg_trigger];
Relation rel;
AclResult aclresult;
Relation tgrel;
SysScanDesc tgscan;
ScanKeyData key;
Relation pgrel;
HeapTuple tuple;
Oid funcrettype;
Oid trigoid;
char internaltrigname[NAMEDATALEN];
char *trigname;
Oid constrrelid = InvalidOid;
ObjectAddress myself,
referenced;
char *oldtablename = NULL;
char *newtablename = NULL;
bool partition_recurse;
if (OidIsValid(relOid))
rel = table_open(relOid, ShareRowExclusiveLock);
else
rel = table_openrv(stmt->relation, ShareRowExclusiveLock);
/*
* Triggers must be on tables or views, and there are additional
* relation-type-specific restrictions.
*/
if (rel->rd_rel->relkind == RELKIND_RELATION)
{
/* Tables can't have INSTEAD OF triggers */
if (stmt->timing != TRIGGER_TYPE_BEFORE &&
stmt->timing != TRIGGER_TYPE_AFTER)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a table",
RelationGetRelationName(rel)),
errdetail("Tables cannot have INSTEAD OF triggers.")));
}
else if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
{
/* Partitioned tables can't have INSTEAD OF triggers */
if (stmt->timing != TRIGGER_TYPE_BEFORE &&
stmt->timing != TRIGGER_TYPE_AFTER)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a table",
RelationGetRelationName(rel)),
errdetail("Tables cannot have INSTEAD OF triggers.")));
/*
* FOR EACH ROW triggers have further restrictions
*/
if (stmt->row)
{
/*
* BEFORE triggers FOR EACH ROW are forbidden, because they would
* allow the user to direct the row to another partition, which
* isn't implemented in the executor.
*/
if (stmt->timing != TRIGGER_TYPE_AFTER)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a partitioned table",
RelationGetRelationName(rel)),
errdetail("Partitioned tables cannot have BEFORE / FOR EACH ROW triggers.")));
/*
* Disallow use of transition tables.
*
* Note that we have another restriction about transition tables
* in partitions; search for 'has_superclass' below for an
* explanation. The check here is just to protect from the fact
* that if we allowed it here, the creation would succeed for a
* partitioned table with no partitions, but would be blocked by
* the other restriction when the first partition was created,
* which is very unfriendly behavior.
*/
if (stmt->transitionRels != NIL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("\"%s\" is a partitioned table",
RelationGetRelationName(rel)),
errdetail("Triggers on partitioned tables cannot have transition tables.")));
}
}
else if (rel->rd_rel->relkind == RELKIND_VIEW)
{
/*
* Greenplum cannot support INSTEAD OF triggers, see merge fixme in
* CheckValidResultRel().
*/
if (stmt->timing == TRIGGER_TYPE_INSTEAD)
ereport(ERROR,
(errcode(ERRCODE_GP_FEATURE_NOT_YET),
errmsg("INSTEAD OF triggers are not supported in Greenplum")));
/*
* Views can have INSTEAD OF triggers (which we check below are
* row-level), or statement-level BEFORE/AFTER triggers.
*/
if (stmt->timing != TRIGGER_TYPE_INSTEAD && stmt->row)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a view",
RelationGetRelationName(rel)),
errdetail("Views cannot have row-level BEFORE or AFTER triggers.")));
/* Disallow TRUNCATE triggers on VIEWs */
if (TRIGGER_FOR_TRUNCATE(stmt->events))
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a view",
RelationGetRelationName(rel)),
errdetail("Views cannot have TRUNCATE triggers.")));
}
else if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
{
if (stmt->timing != TRIGGER_TYPE_BEFORE &&
stmt->timing != TRIGGER_TYPE_AFTER)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a foreign table",
RelationGetRelationName(rel)),
errdetail("Foreign tables cannot have INSTEAD OF triggers.")));
if (TRIGGER_FOR_TRUNCATE(stmt->events))
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a foreign table",
RelationGetRelationName(rel)),
errdetail("Foreign tables cannot have TRUNCATE triggers.")));
/*
* We disallow constraint triggers to protect the assumption that
* triggers on FKs can't be deferred. See notes with AfterTriggers
* data structures, below.
*/
if (stmt->isconstraint)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a foreign table",
RelationGetRelationName(rel)),
errdetail("Foreign tables cannot have constraint triggers.")));
}
else
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a table or view",
RelationGetRelationName(rel))));
if (!allowSystemTableMods && IsSystemRelation(rel))
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied: \"%s\" is a system catalog",
RelationGetRelationName(rel))));
if (stmt->isconstraint)
{
/*
* We must take a lock on the target relation to protect against
* concurrent drop. It's not clear that AccessShareLock is strong
* enough, but we certainly need at least that much... otherwise, we
* might end up creating a pg_constraint entry referencing a
* nonexistent table.
*/
if (OidIsValid(refRelOid))
{
LockRelationOid(refRelOid, AccessShareLock);
constrrelid = refRelOid;
}
else if (stmt->constrrel != NULL)
constrrelid = RangeVarGetRelid(stmt->constrrel, AccessShareLock,
false);
}
/* permission checks */
if (!isInternal)
{
aclresult = pg_class_aclcheck(RelationGetRelid(rel), GetUserId(),
ACL_TRIGGER);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, get_relkind_objtype(rel->rd_rel->relkind),
RelationGetRelationName(rel));
if (OidIsValid(constrrelid))
{
aclresult = pg_class_aclcheck(constrrelid, GetUserId(),
ACL_TRIGGER);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, get_relkind_objtype(get_rel_relkind(constrrelid)),
get_rel_name(constrrelid));
}
}
/*
* When called on a partitioned table to create a FOR EACH ROW trigger
* that's not internal, we create one trigger for each partition, too.
*
* For that, we'd better hold lock on all of them ahead of time.
*/
partition_recurse = !isInternal && stmt->row &&
rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE;
if (partition_recurse)
list_free(find_all_inheritors(RelationGetRelid(rel),
ShareRowExclusiveLock, NULL));
/* Compute tgtype */
TRIGGER_CLEAR_TYPE(tgtype);
if (stmt->row)
TRIGGER_SETT_ROW(tgtype);
tgtype |= stmt->timing;
tgtype |= stmt->events;
/* Disallow ROW-level TRUNCATE triggers */
if (TRIGGER_FOR_ROW(tgtype) && TRIGGER_FOR_TRUNCATE(tgtype))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("TRUNCATE FOR EACH ROW triggers are not supported")));
/* INSTEAD triggers must be row-level, and can't have WHEN or columns */
if (TRIGGER_FOR_INSTEAD(tgtype))
{
if (!TRIGGER_FOR_ROW(tgtype))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("INSTEAD OF triggers must be FOR EACH ROW")));
if (stmt->whenClause)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("INSTEAD OF triggers cannot have WHEN conditions")));
if (stmt->columns != NIL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("INSTEAD OF triggers cannot have column lists")));
}
/*
* We don't yet support naming ROW transition variables, but the parser
* recognizes the syntax so we can give a nicer message here.
*
* Per standard, REFERENCING TABLE names are only allowed on AFTER
* triggers. Per standard, REFERENCING ROW names are not allowed with FOR
* EACH STATEMENT. Per standard, each OLD/NEW, ROW/TABLE permutation is
* only allowed once. Per standard, OLD may not be specified when
* creating a trigger only for INSERT, and NEW may not be specified when
* creating a trigger only for DELETE.
*
* Notice that the standard allows an AFTER ... FOR EACH ROW trigger to
* reference both ROW and TABLE transition data.
*/
if (stmt->transitionRels != NIL)
{
List *varList = stmt->transitionRels;
ListCell *lc;
foreach(lc, varList)
{
TriggerTransition *tt = lfirst_node(TriggerTransition, lc);
if (!(tt->isTable))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("ROW variable naming in the REFERENCING clause is not supported"),
errhint("Use OLD TABLE or NEW TABLE for naming transition tables.")));
/*
* Because of the above test, we omit further ROW-related testing
* below. If we later allow naming OLD and NEW ROW variables,
* adjustments will be needed below.
*/
if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a foreign table",
RelationGetRelationName(rel)),
errdetail("Triggers on foreign tables cannot have transition tables.")));
if (rel->rd_rel->relkind == RELKIND_VIEW)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a view",
RelationGetRelationName(rel)),
errdetail("Triggers on views cannot have transition tables.")));
/*
* We currently don't allow row-level triggers with transition
* tables on partition or inheritance children. Such triggers
* would somehow need to see tuples converted to the format of the
* table they're attached to, and it's not clear which subset of
* tuples each child should see. See also the prohibitions in
* ATExecAttachPartition() and ATExecAddInherit().
*/
if (TRIGGER_FOR_ROW(tgtype) && has_superclass(rel->rd_id))
{
/* Use appropriate error message. */
if (rel->rd_rel->relispartition)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("ROW triggers with transition tables are not supported on partitions")));
else
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("ROW triggers with transition tables are not supported on inheritance children")));
}
if (stmt->timing != TRIGGER_TYPE_AFTER)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("transition table name can only be specified for an AFTER trigger")));
if (TRIGGER_FOR_TRUNCATE(tgtype))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("TRUNCATE triggers with transition tables are not supported")));
/*
* We currently don't allow multi-event triggers ("INSERT OR
* UPDATE") with transition tables, because it's not clear how to
* handle INSERT ... ON CONFLICT statements which can fire both
* INSERT and UPDATE triggers. We show the inserted tuples to
* INSERT triggers and the updated tuples to UPDATE triggers, but
* it's not yet clear what INSERT OR UPDATE trigger should see.
* This restriction could be lifted if we can decide on the right
* semantics in a later release.
*/
if (((TRIGGER_FOR_INSERT(tgtype) ? 1 : 0) +
(TRIGGER_FOR_UPDATE(tgtype) ? 1 : 0) +
(TRIGGER_FOR_DELETE(tgtype) ? 1 : 0)) != 1)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("transition tables cannot be specified for triggers with more than one event")));
/*
* We currently don't allow column-specific triggers with
* transition tables. Per spec, that seems to require
* accumulating separate transition tables for each combination of
* columns, which is a lot of work for a rather marginal feature.
*/
if (stmt->columns != NIL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("transition tables cannot be specified for triggers with column lists")));
/*
* We disallow constraint triggers with transition tables, to
* protect the assumption that such triggers can't be deferred.
* See notes with AfterTriggers data structures, below.
*
* Currently this is enforced by the grammar, so just Assert here.
*/
Assert(!stmt->isconstraint);
if (tt->isNew)
{
if (!(TRIGGER_FOR_INSERT(tgtype) ||
TRIGGER_FOR_UPDATE(tgtype)))
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("NEW TABLE can only be specified for an INSERT or UPDATE trigger")));
if (newtablename != NULL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("NEW TABLE cannot be specified multiple times")));
newtablename = tt->name;
}
else
{
if (!(TRIGGER_FOR_DELETE(tgtype) ||
TRIGGER_FOR_UPDATE(tgtype)))
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("OLD TABLE can only be specified for a DELETE or UPDATE trigger")));
if (oldtablename != NULL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("OLD TABLE cannot be specified multiple times")));
oldtablename = tt->name;
}
}
if (newtablename != NULL && oldtablename != NULL &&
strcmp(newtablename, oldtablename) == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("OLD TABLE name and NEW TABLE name cannot be the same")));
}
/*
* Parse the WHEN clause, if any and we weren't passed an already
* transformed one.
*
* Note that as a side effect, we fill whenRtable when parsing. If we got
* an already parsed clause, this does not occur, which is what we want --
* no point in adding redundant dependencies below.
*/
if (!whenClause && stmt->whenClause)
{
ParseState *pstate;
RangeTblEntry *rte;
List *varList;
ListCell *lc;
/* Set up a pstate to parse with */
pstate = make_parsestate(NULL);
pstate->p_sourcetext = queryString;
/*
* Set up RTEs for OLD and NEW references.
*
* 'OLD' must always have varno equal to 1 and 'NEW' equal to 2.
*/
rte = addRangeTableEntryForRelation(pstate, rel,
AccessShareLock,
makeAlias("old", NIL),
false, false);
addRTEtoQuery(pstate, rte, false, true, true);
rte = addRangeTableEntryForRelation(pstate, rel,
AccessShareLock,
makeAlias("new", NIL),
false, false);
addRTEtoQuery(pstate, rte, false, true, true);
/* Transform expression. Copy to be sure we don't modify original */
whenClause = transformWhereClause(pstate,
copyObject(stmt->whenClause),
EXPR_KIND_TRIGGER_WHEN,
"WHEN");
/* we have to fix its collations too */
assign_expr_collations(pstate, whenClause);
/*
* Check for disallowed references to OLD/NEW.
*
* NB: pull_var_clause is okay here only because we don't allow
* subselects in WHEN clauses; it would fail to examine the contents
* of subselects.
*/
varList = pull_var_clause(whenClause, 0);
foreach(lc, varList)
{
Var *var = (Var *) lfirst(lc);
switch (var->varno)
{
case PRS2_OLD_VARNO:
if (!TRIGGER_FOR_ROW(tgtype))
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("statement trigger's WHEN condition cannot reference column values"),
parser_errposition(pstate, var->location)));
if (TRIGGER_FOR_INSERT(tgtype))
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("INSERT trigger's WHEN condition cannot reference OLD values"),
parser_errposition(pstate, var->location)));
/* system columns are okay here */
break;
case PRS2_NEW_VARNO:
if (!TRIGGER_FOR_ROW(tgtype))
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("statement trigger's WHEN condition cannot reference column values"),
parser_errposition(pstate, var->location)));
if (TRIGGER_FOR_DELETE(tgtype))
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("DELETE trigger's WHEN condition cannot reference NEW values"),
parser_errposition(pstate, var->location)));
if (var->varattno < 0 && TRIGGER_FOR_BEFORE(tgtype))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("BEFORE trigger's WHEN condition cannot reference NEW system columns"),
parser_errposition(pstate, var->location)));
if (TRIGGER_FOR_BEFORE(tgtype) &&
var->varattno == 0 &&
RelationGetDescr(rel)->constr &&
RelationGetDescr(rel)->constr->has_generated_stored)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("BEFORE trigger's WHEN condition cannot reference NEW generated columns"),
errdetail("A whole-row reference is used and the table contains generated columns."),
parser_errposition(pstate, var->location)));
if (TRIGGER_FOR_BEFORE(tgtype) &&
var->varattno > 0 &&
TupleDescAttr(RelationGetDescr(rel), var->varattno - 1)->attgenerated)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("BEFORE trigger's WHEN condition cannot reference NEW generated columns"),
errdetail("Column \"%s\" is a generated column.",
NameStr(TupleDescAttr(RelationGetDescr(rel), var->varattno - 1)->attname)),
parser_errposition(pstate, var->location)));
break;
default:
/* can't happen without add_missing_from, so just elog */
elog(ERROR, "trigger WHEN condition cannot contain references to other relations");
break;
}
}
/* we'll need the rtable for recordDependencyOnExpr */
whenRtable = pstate->p_rtable;
qual = nodeToString(whenClause);
free_parsestate(pstate);
}
else if (!whenClause)
{
whenClause = NULL;
whenRtable = NIL;
qual = NULL;
}
else
{
qual = nodeToString(whenClause);
whenRtable = NIL;
}
/*
* Find and validate the trigger function.
*/
if (!OidIsValid(funcoid))
funcoid = LookupFuncName(stmt->funcname, 0, NULL, false);
if (!isInternal)
{
aclresult = pg_proc_aclcheck(funcoid, GetUserId(), ACL_EXECUTE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, OBJECT_FUNCTION,
NameListToString(stmt->funcname));
}
funcrettype = get_func_rettype(funcoid);
if (funcrettype != TRIGGEROID)
{
/*
* We allow OPAQUE just so we can load old dump files. When we see a
* trigger function declared OPAQUE, change it to TRIGGER.
*/
if (funcrettype == OPAQUEOID)
{
if (Gp_role != GP_ROLE_EXECUTE)
ereport(WARNING,
(errmsg("changing return type of function %s from %s to %s",
NameListToString(stmt->funcname),
"opaque", "trigger")));
SetFunctionReturnType(funcoid, TRIGGEROID);
}
else
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("function %s must return type %s",
NameListToString(stmt->funcname), "trigger")));
}
/* Check GPDB limitations */
if (RelationIsAppendOptimized(rel) &&
TRIGGER_FOR_ROW(tgtype) &&
!stmt->isconstraint)
{
if (TRIGGER_FOR_UPDATE(tgtype))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("ON UPDATE triggers are not supported on append-only tables")));
if (TRIGGER_FOR_DELETE(tgtype))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("ON DELETE triggers are not supported on append-only tables")));
}
/*
* If the command is a user-entered CREATE CONSTRAINT TRIGGER command that
* references one of the built-in RI_FKey trigger functions, assume it is
* from a dump of a pre-7.3 foreign key constraint, and take steps to
* convert this legacy representation into a regular foreign key
* constraint. Ugly, but necessary for loading old dump files.
*/
if (stmt->isconstraint && !isInternal &&
list_length(stmt->args) >= 6 &&
(list_length(stmt->args) % 2) == 0 &&
RI_FKey_trigger_type(funcoid) != RI_TRIGGER_NONE)
{
/* Keep lock on target rel until end of xact */
table_close(rel, NoLock);
ConvertTriggerToFK(stmt, funcoid);
return InvalidObjectAddress;
}
/*
* If it's a user-entered CREATE CONSTRAINT TRIGGER command, make a
* corresponding pg_constraint entry.
*/
if (stmt->isconstraint && !OidIsValid(constraintOid))
{
/* Internal callers should have made their own constraints */
Assert(!isInternal);
constraintOid = CreateConstraintEntry(stmt->trigname,
RelationGetNamespace(rel),
CONSTRAINT_TRIGGER,
stmt->deferrable,
stmt->initdeferred,
true,
InvalidOid, /* no parent */
RelationGetRelid(rel),
NULL, /* no conkey */
0,
0,
InvalidOid, /* no domain */
InvalidOid, /* no index */
InvalidOid, /* no foreign key */
NULL,
NULL,
NULL,
NULL,
0,
' ',
' ',
' ',
NULL, /* no exclusion */
NULL, /* no check constraint */
NULL,
true, /* islocal */
0, /* inhcount */
true, /* isnoinherit */
isInternal); /* is_internal */
}
/*
* Generate the trigger's OID now, so that we can use it in the name if
* needed.
*/
tgrel = table_open(TriggerRelationId, RowExclusiveLock);
/*
* For RI constraint triggers, the trigger's name is derived from the
* trigger OID. That creates a chicken-and-egg problem with the usual
* GPDB OID dispatching mechanism. In a QE, we cannot look up the
* trigger OID to use by trigger name, because the trigger name is
* derived from the OID. To work around that, we use more fields as
* the key. For a user-defined trigger, tgrelid and the trigger name
* should be enough. For internal triggers, we use the name prefix
* together with constraint OID and function OID. That should be
* unique: there should be no need to have more than one internal trigger
* with same function for one constraint.
*/
trigoid = GetNewOidForTrigger(tgrel, TriggerOidIndexId,
Anum_pg_trigger_oid,
RelationGetRelid(rel),
stmt->trigname,
constraintOid,
funcoid);
/*
* If trigger is internally generated, modify the provided trigger name to
* ensure uniqueness by appending the trigger OID. (Callers will usually
* supply a simple constant trigger name in these cases.)
*/
if (isInternal)
{
snprintf(internaltrigname, sizeof(internaltrigname),
"%s_%u", stmt->trigname, trigoid);
trigname = internaltrigname;
}
else
{
/* user-defined trigger; use the specified trigger name as-is */
trigname = stmt->trigname;
}
/*
* Scan pg_trigger for existing triggers on relation. We do this only to
* give a nice error message if there's already a trigger of the same
* name. (The unique index on tgrelid/tgname would complain anyway.) We
* can skip this for internally generated triggers, since the name
* modification above should be sufficient.
*
* NOTE that this is cool only because we have ShareRowExclusiveLock on
* the relation, so the trigger set won't be changing underneath us.
*/
if (!isInternal)
{
ScanKeyInit(&key,
Anum_pg_trigger_tgrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(rel)));
tgscan = systable_beginscan(tgrel, TriggerRelidNameIndexId, true,
NULL, 1, &key);
while (HeapTupleIsValid(tuple = systable_getnext(tgscan)))
{
Form_pg_trigger pg_trigger = (Form_pg_trigger) GETSTRUCT(tuple);
if (namestrcmp(&(pg_trigger->tgname), trigname) == 0)
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("trigger \"%s\" for relation \"%s\" already exists",
trigname, RelationGetRelationName(rel))));
}
systable_endscan(tgscan);
}
/*
* Build the new pg_trigger tuple.
*
* When we're creating a trigger in a partition, we mark it as internal,
* even though we don't do the isInternal magic in this function. This
* makes the triggers in partitions identical to the ones in the
* partitioned tables, except that they are marked internal.
*/
memset(nulls, false, sizeof(nulls));
values[Anum_pg_trigger_oid - 1] = ObjectIdGetDatum(trigoid);
values[Anum_pg_trigger_tgrelid - 1] = ObjectIdGetDatum(RelationGetRelid(rel));
values[Anum_pg_trigger_tgname - 1] = DirectFunctionCall1(namein,
CStringGetDatum(trigname));
values[Anum_pg_trigger_tgfoid - 1] = ObjectIdGetDatum(funcoid);
values[Anum_pg_trigger_tgtype - 1] = Int16GetDatum(tgtype);
/*
* Special for Greenplum Database: Ignore foreign keys for now. Create
* the triggers to back them as 'disabled'.
*/
char tgenabled = TRIGGER_FIRES_ON_ORIGIN;
if (isInternal)
{
if (RI_FKey_trigger_type(funcoid))
{
tgenabled = TRIGGER_DISABLED;
}
else if (funcoid == F_UNIQUE_KEY_RECHECK)
{
/*
* unique_key_recheck is used for deferrable unique constraints.
* We do enforce unique constraints.
*/
}
else
elog(WARNING, "unrecognized internal trigger function %u", funcoid);
}
values[Anum_pg_trigger_tgenabled - 1] = CharGetDatum(tgenabled);
values[Anum_pg_trigger_tgisinternal - 1] = BoolGetDatum(isInternal || in_partition);
values[Anum_pg_trigger_tgconstrrelid - 1] = ObjectIdGetDatum(constrrelid);
values[Anum_pg_trigger_tgconstrindid - 1] = ObjectIdGetDatum(indexOid);
values[Anum_pg_trigger_tgconstraint - 1] = ObjectIdGetDatum(constraintOid);
values[Anum_pg_trigger_tgdeferrable - 1] = BoolGetDatum(stmt->deferrable);
values[Anum_pg_trigger_tginitdeferred - 1] = BoolGetDatum(stmt->initdeferred);
if (stmt->args)
{
ListCell *le;
char *args;
int16 nargs = list_length(stmt->args);
int len = 0;
foreach(le, stmt->args)
{
char *ar = strVal(lfirst(le));
len += strlen(ar) + 4;
for (; *ar; ar++)
{
if (*ar == '\\')
len++;
}
}
args = (char *) palloc(len + 1);
args[0] = '\0';
foreach(le, stmt->args)
{
char *s = strVal(lfirst(le));
char *d = args + strlen(args);
while (*s)
{
if (*s == '\\')
*d++ = '\\';
*d++ = *s++;
}
strcpy(d, "\\000");
}
values[Anum_pg_trigger_tgnargs - 1] = Int16GetDatum(nargs);
values[Anum_pg_trigger_tgargs - 1] = DirectFunctionCall1(byteain,
CStringGetDatum(args));
}
else
{
values[Anum_pg_trigger_tgnargs - 1] = Int16GetDatum(0);
values[Anum_pg_trigger_tgargs - 1] = DirectFunctionCall1(byteain,
CStringGetDatum(""));
}
/* build column number array if it's a column-specific trigger */
ncolumns = list_length(stmt->columns);
if (ncolumns == 0)
columns = NULL;
else
{
ListCell *cell;
int i = 0;
columns = (int16 *) palloc(ncolumns * sizeof(int16));
foreach(cell, stmt->columns)
{
char *name = strVal(lfirst(cell));
int16 attnum;
int j;
/* Lookup column name. System columns are not allowed */
attnum = attnameAttNum(rel, name, false);
if (attnum == InvalidAttrNumber)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" of relation \"%s\" does not exist",
name, RelationGetRelationName(rel))));
/* Check for duplicates */
for (j = i - 1; j >= 0; j--)
{
if (columns[j] == attnum)
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_COLUMN),
errmsg("column \"%s\" specified more than once",
name)));
}
columns[i++] = attnum;
}
}
tgattr = buildint2vector(columns, ncolumns);
values[Anum_pg_trigger_tgattr - 1] = PointerGetDatum(tgattr);
/* set tgqual if trigger has WHEN clause */
if (qual)
values[Anum_pg_trigger_tgqual - 1] = CStringGetTextDatum(qual);
else
nulls[Anum_pg_trigger_tgqual - 1] = true;
if (oldtablename)
values[Anum_pg_trigger_tgoldtable - 1] = DirectFunctionCall1(namein,
CStringGetDatum(oldtablename));
else
nulls[Anum_pg_trigger_tgoldtable - 1] = true;
if (newtablename)
values[Anum_pg_trigger_tgnewtable - 1] = DirectFunctionCall1(namein,
CStringGetDatum(newtablename));
else
nulls[Anum_pg_trigger_tgnewtable - 1] = true;
tuple = heap_form_tuple(tgrel->rd_att, values, nulls);
/*
* Insert tuple into pg_trigger.
*/
CatalogTupleInsert(tgrel, tuple);
heap_freetuple(tuple);
table_close(tgrel, RowExclusiveLock);
pfree(DatumGetPointer(values[Anum_pg_trigger_tgname - 1]));
pfree(DatumGetPointer(values[Anum_pg_trigger_tgargs - 1]));
pfree(DatumGetPointer(values[Anum_pg_trigger_tgattr - 1]));
if (oldtablename)
pfree(DatumGetPointer(values[Anum_pg_trigger_tgoldtable - 1]));
if (newtablename)
pfree(DatumGetPointer(values[Anum_pg_trigger_tgnewtable - 1]));
/*
* Update relation's pg_class entry; if necessary; and if not, send an SI
* message to make other backends (and this one) rebuild relcache entries.
*/
pgrel = table_open(RelationRelationId, RowExclusiveLock);
tuple = SearchSysCacheCopy1(RELOID,
ObjectIdGetDatum(RelationGetRelid(rel)));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for relation %u",
RelationGetRelid(rel));
if (!((Form_pg_class) GETSTRUCT(tuple))->relhastriggers)
{
((Form_pg_class) GETSTRUCT(tuple))->relhastriggers = true;
CatalogTupleUpdate(pgrel, &tuple->t_self, tuple);
CommandCounterIncrement();
}
else
CacheInvalidateRelcacheByTuple(tuple);
heap_freetuple(tuple);
table_close(pgrel, RowExclusiveLock);
/*
* Record dependencies for trigger. Always place a normal dependency on
* the function.
*/
myself.classId = TriggerRelationId;
myself.objectId = trigoid;
myself.objectSubId = 0;
referenced.classId = ProcedureRelationId;
referenced.objectId = funcoid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
if (isInternal && OidIsValid(constraintOid))
{
/*
* Internally-generated trigger for a constraint, so make it an
* internal dependency of the constraint. We can skip depending on
* the relation(s), as there'll be an indirect dependency via the
* constraint.
*/
referenced.classId = ConstraintRelationId;
referenced.objectId = constraintOid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_INTERNAL);
}
else
{
/*
* User CREATE TRIGGER, so place dependencies. We make trigger be
* auto-dropped if its relation is dropped or if the FK relation is
* dropped. (Auto drop is compatible with our pre-7.3 behavior.)
*/
referenced.classId = RelationRelationId;
referenced.objectId = RelationGetRelid(rel);
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_AUTO);
if (OidIsValid(constrrelid))
{
referenced.classId = RelationRelationId;
referenced.objectId = constrrelid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_AUTO);
}
/* Not possible to have an index dependency in this case */
Assert(!OidIsValid(indexOid));
/*
* If it's a user-specified constraint trigger, make the constraint
* internally dependent on the trigger instead of vice versa.
*/
if (OidIsValid(constraintOid))
{
referenced.classId = ConstraintRelationId;
referenced.objectId = constraintOid;
referenced.objectSubId = 0;
recordDependencyOn(&referenced, &myself, DEPENDENCY_INTERNAL);
}
/*
* If it's a partition trigger, create the partition dependencies.
*/
if (OidIsValid(parentTriggerOid))
{
ObjectAddressSet(referenced, TriggerRelationId, parentTriggerOid);
recordDependencyOn(&myself, &referenced, DEPENDENCY_PARTITION_PRI);
ObjectAddressSet(referenced, RelationRelationId, RelationGetRelid(rel));
recordDependencyOn(&myself, &referenced, DEPENDENCY_PARTITION_SEC);
}
}
/* If column-specific trigger, add normal dependencies on columns */
if (columns != NULL)
{
int i;
referenced.classId = RelationRelationId;
referenced.objectId = RelationGetRelid(rel);
for (i = 0; i < ncolumns; i++)
{
referenced.objectSubId = columns[i];
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
}
/*
* If it has a WHEN clause, add dependencies on objects mentioned in the
* expression (eg, functions, as well as any columns used).
*/
if (whenRtable != NIL)
recordDependencyOnExpr(&myself, whenClause, whenRtable,
DEPENDENCY_NORMAL);
/* Post creation hook for new trigger */
InvokeObjectPostCreateHookArg(TriggerRelationId, trigoid, 0,
isInternal);
/*
* Lastly, create the trigger on child relations, if needed.
*/
if (partition_recurse)
{
PartitionDesc partdesc = RelationGetPartitionDesc(rel);
List *idxs = NIL;
List *childTbls = NIL;
ListCell *l;
int i;
MemoryContext oldcxt,
perChildCxt;
perChildCxt = AllocSetContextCreate(CurrentMemoryContext,
"part trig clone",
ALLOCSET_SMALL_SIZES);
/*
* When a trigger is being created associated with an index, we'll
* need to associate the trigger in each child partition with the
* corresponding index on it.
*/
if (OidIsValid(indexOid))
{
ListCell *l;
List *idxs = NIL;
idxs = find_inheritance_children(indexOid, ShareRowExclusiveLock);
foreach(l, idxs)
childTbls = lappend_oid(childTbls,
IndexGetRelation(lfirst_oid(l),
false));
}
oldcxt = MemoryContextSwitchTo(perChildCxt);
/* Iterate to create the trigger on each existing partition */
for (i = 0; i < partdesc->nparts; i++)
{
Oid indexOnChild = InvalidOid;
ListCell *l2;
CreateTrigStmt *childStmt;
Relation childTbl;
Node *qual;
bool found_whole_row;
childTbl = table_open(partdesc->oids[i], ShareRowExclusiveLock);
/* Find which of the child indexes is the one on this partition */
if (OidIsValid(indexOid))
{
forboth(l, idxs, l2, childTbls)
{
if (lfirst_oid(l2) == partdesc->oids[i])
{
indexOnChild = lfirst_oid(l);
break;
}
}
if (!OidIsValid(indexOnChild))
elog(ERROR, "failed to find index matching index \"%s\" in partition \"%s\"",
get_rel_name(indexOid),
get_rel_name(partdesc->oids[i]));
}
/*
* Initialize our fabricated parse node by copying the original
* one, then resetting fields that we pass separately.
*/
childStmt = (CreateTrigStmt *) copyObject(stmt);
childStmt->funcname = NIL;
childStmt->args = NIL;
childStmt->whenClause = NULL;
/* If there is a WHEN clause, create a modified copy of it */
qual = copyObject(whenClause);
qual = (Node *)
map_partition_varattnos((List *) qual, PRS2_OLD_VARNO,
childTbl, rel,
&found_whole_row);
if (found_whole_row)
elog(ERROR, "unexpected whole-row reference found in trigger WHEN clause");
qual = (Node *)
map_partition_varattnos((List *) qual, PRS2_NEW_VARNO,
childTbl, rel,
&found_whole_row);
if (found_whole_row)
elog(ERROR, "unexpected whole-row reference found in trigger WHEN clause");
CreateTrigger(childStmt, queryString,
partdesc->oids[i], refRelOid,
InvalidOid, indexOnChild,
funcoid, trigoid, qual,
isInternal, true);
table_close(childTbl, NoLock);
MemoryContextReset(perChildCxt);
}
MemoryContextSwitchTo(oldcxt);
MemoryContextDelete(perChildCxt);
list_free(idxs);
list_free(childTbls);
}
/* Keep lock on target rel until end of xact */
table_close(rel, NoLock);
return myself;
}
/*
* Convert legacy (pre-7.3) CREATE CONSTRAINT TRIGGER commands into
* full-fledged foreign key constraints.
*
* The conversion is complex because a pre-7.3 foreign key involved three
* separate triggers, which were reported separately in dumps. While the
* single trigger on the referencing table adds no new information, we need
* to know the trigger functions of both of the triggers on the referenced
* table to build the constraint declaration. Also, due to lack of proper
* dependency checking pre-7.3, it is possible that the source database had
* an incomplete set of triggers resulting in an only partially enforced
* FK constraint. (This would happen if one of the tables had been dropped
* and re-created, but only if the DB had been affected by a 7.0 pg_dump bug
* that caused loss of tgconstrrelid information.) We choose to translate to
* an FK constraint only when we've seen all three triggers of a set. This is
* implemented by storing unmatched items in a list in TopMemoryContext.
* We match triggers together by comparing the trigger arguments (which
* include constraint name, table and column names, so should be good enough).
*/
typedef struct
{
List *args; /* list of (T_String) Values or NIL */
Oid funcoids[3]; /* OIDs of trigger functions */
/* The three function OIDs are stored in the order update, delete, child */
} OldTriggerInfo;
static void
ConvertTriggerToFK(CreateTrigStmt *stmt, Oid funcoid)
{
static List *info_list = NIL;
static const char *const funcdescr[3] = {
gettext_noop("Found referenced table's UPDATE trigger."),
gettext_noop("Found referenced table's DELETE trigger."),
gettext_noop("Found referencing table's trigger.")
};
char *constr_name;
char *fk_table_name;
char *pk_table_name;
char fk_matchtype = FKCONSTR_MATCH_SIMPLE;
List *fk_attrs = NIL;
List *pk_attrs = NIL;
StringInfoData buf;
int funcnum;
OldTriggerInfo *info = NULL;
ListCell *l;
int i;
/* Parse out the trigger arguments */
constr_name = strVal(linitial(stmt->args));
fk_table_name = strVal(lsecond(stmt->args));
pk_table_name = strVal(lthird(stmt->args));
i = 0;
foreach(l, stmt->args)
{
Value *arg = (Value *) lfirst(l);
i++;
if (i < 4) /* skip constraint and table names */
continue;
if (i == 4) /* handle match type */
{
if (strcmp(strVal(arg), "FULL") == 0)
fk_matchtype = FKCONSTR_MATCH_FULL;
else
fk_matchtype = FKCONSTR_MATCH_SIMPLE;
continue;
}
if (i % 2)
fk_attrs = lappend(fk_attrs, arg);
else
pk_attrs = lappend(pk_attrs, arg);
}
/* Prepare description of constraint for use in messages */
initStringInfo(&buf);
appendStringInfo(&buf, "FOREIGN KEY %s(",
quote_identifier(fk_table_name));
i = 0;
foreach(l, fk_attrs)
{
Value *arg = (Value *) lfirst(l);
if (i++ > 0)
appendStringInfoChar(&buf, ',');
appendStringInfoString(&buf, quote_identifier(strVal(arg)));
}
appendStringInfo(&buf, ") REFERENCES %s(",
quote_identifier(pk_table_name));
i = 0;
foreach(l, pk_attrs)
{
Value *arg = (Value *) lfirst(l);
if (i++ > 0)
appendStringInfoChar(&buf, ',');
appendStringInfoString(&buf, quote_identifier(strVal(arg)));
}
appendStringInfoChar(&buf, ')');
/* Identify class of trigger --- update, delete, or referencing-table */
switch (funcoid)
{
case F_RI_FKEY_CASCADE_UPD:
case F_RI_FKEY_RESTRICT_UPD:
case F_RI_FKEY_SETNULL_UPD:
case F_RI_FKEY_SETDEFAULT_UPD:
case F_RI_FKEY_NOACTION_UPD:
funcnum = 0;
break;
case F_RI_FKEY_CASCADE_DEL:
case F_RI_FKEY_RESTRICT_DEL:
case F_RI_FKEY_SETNULL_DEL:
case F_RI_FKEY_SETDEFAULT_DEL:
case F_RI_FKEY_NOACTION_DEL:
funcnum = 1;
break;
default:
funcnum = 2;
break;
}
/* See if we have a match to this trigger */
foreach(l, info_list)
{
info = (OldTriggerInfo *) lfirst(l);
if (info->funcoids[funcnum] == InvalidOid &&
equal(info->args, stmt->args))
{
info->funcoids[funcnum] = funcoid;
break;
}
}
if (l == NULL)
{
/* First trigger of set, so create a new list entry */
MemoryContext oldContext;
ereport(NOTICE,
(errmsg("ignoring incomplete trigger group for constraint \"%s\" %s",
constr_name, buf.data),
errdetail_internal("%s", _(funcdescr[funcnum]))));
oldContext = MemoryContextSwitchTo(TopMemoryContext);
info = (OldTriggerInfo *) palloc0(sizeof(OldTriggerInfo));
info->args = copyObject(stmt->args);
info->funcoids[funcnum] = funcoid;
info_list = lappend(info_list, info);
MemoryContextSwitchTo(oldContext);
}
else if (info->funcoids[0] == InvalidOid ||
info->funcoids[1] == InvalidOid ||
info->funcoids[2] == InvalidOid)
{
/* Second trigger of set */
ereport(NOTICE,
(errmsg("ignoring incomplete trigger group for constraint \"%s\" %s",
constr_name, buf.data),
errdetail_internal("%s", _(funcdescr[funcnum]))));
}
else
{
/* OK, we have a set, so make the FK constraint ALTER TABLE cmd */
AlterTableStmt *atstmt = makeNode(AlterTableStmt);
AlterTableCmd *atcmd = makeNode(AlterTableCmd);
Constraint *fkcon = makeNode(Constraint);
PlannedStmt *wrapper = makeNode(PlannedStmt);
ereport(NOTICE,
(errmsg("converting trigger group into constraint \"%s\" %s",
constr_name, buf.data),
errdetail_internal("%s", _(funcdescr[funcnum]))));
fkcon->contype = CONSTR_FOREIGN;
fkcon->location = -1;
if (funcnum == 2)
{
/* This trigger is on the FK table */
atstmt->relation = stmt->relation;
if (stmt->constrrel)
fkcon->pktable = stmt->constrrel;
else
{
/* Work around ancient pg_dump bug that omitted constrrel */
fkcon->pktable = makeRangeVar(NULL, pk_table_name, -1);
}
}
else
{
/* This trigger is on the PK table */
fkcon->pktable = stmt->relation;
if (stmt->constrrel)
atstmt->relation = stmt->constrrel;
else
{
/* Work around ancient pg_dump bug that omitted constrrel */
atstmt->relation = makeRangeVar(NULL, fk_table_name, -1);
}
}
atstmt->cmds = list_make1(atcmd);
atstmt->relkind = OBJECT_TABLE;
atcmd->subtype = AT_AddConstraint;
atcmd->def = (Node *) fkcon;
if (strcmp(constr_name, "<unnamed>") == 0)
fkcon->conname = NULL;
else
fkcon->conname = constr_name;
fkcon->fk_attrs = fk_attrs;
fkcon->pk_attrs = pk_attrs;
fkcon->fk_matchtype = fk_matchtype;
switch (info->funcoids[0])
{
case F_RI_FKEY_NOACTION_UPD:
fkcon->fk_upd_action = FKCONSTR_ACTION_NOACTION;
break;
case F_RI_FKEY_CASCADE_UPD:
fkcon->fk_upd_action = FKCONSTR_ACTION_CASCADE;
break;
case F_RI_FKEY_RESTRICT_UPD:
fkcon->fk_upd_action = FKCONSTR_ACTION_RESTRICT;
break;
case F_RI_FKEY_SETNULL_UPD:
fkcon->fk_upd_action = FKCONSTR_ACTION_SETNULL;
break;
case F_RI_FKEY_SETDEFAULT_UPD:
fkcon->fk_upd_action = FKCONSTR_ACTION_SETDEFAULT;
break;
default:
/* can't get here because of earlier checks */
elog(ERROR, "confused about RI update function");
}
switch (info->funcoids[1])
{
case F_RI_FKEY_NOACTION_DEL:
fkcon->fk_del_action = FKCONSTR_ACTION_NOACTION;
break;
case F_RI_FKEY_CASCADE_DEL:
fkcon->fk_del_action = FKCONSTR_ACTION_CASCADE;
break;
case F_RI_FKEY_RESTRICT_DEL:
fkcon->fk_del_action = FKCONSTR_ACTION_RESTRICT;
break;
case F_RI_FKEY_SETNULL_DEL:
fkcon->fk_del_action = FKCONSTR_ACTION_SETNULL;
break;
case F_RI_FKEY_SETDEFAULT_DEL:
fkcon->fk_del_action = FKCONSTR_ACTION_SETDEFAULT;
break;
default:
/* can't get here because of earlier checks */
elog(ERROR, "confused about RI delete function");
}
fkcon->deferrable = stmt->deferrable;
fkcon->initdeferred = stmt->initdeferred;
fkcon->skip_validation = false;
fkcon->initially_valid = true;
/* finally, wrap it in a dummy PlannedStmt */
wrapper->commandType = CMD_UTILITY;
wrapper->canSetTag = false;
wrapper->utilityStmt = (Node *) atstmt;
wrapper->stmt_location = -1;
wrapper->stmt_len = -1;
/* ... and execute it */
ProcessUtility(wrapper,
"(generated ALTER TABLE ADD FOREIGN KEY command)",
PROCESS_UTILITY_SUBCOMMAND, NULL, NULL,
None_Receiver, NULL);
/* Remove the matched item from the list */
info_list = list_delete_ptr(info_list, info);
pfree(info);
/* We leak the copied args ... not worth worrying about */
}
}
/*
* Guts of trigger deletion.
*/
void
RemoveTriggerById(Oid trigOid)
{
Relation tgrel;
SysScanDesc tgscan;
ScanKeyData skey[1];
HeapTuple tup;
Oid relid;
Relation rel;
tgrel = table_open(TriggerRelationId, RowExclusiveLock);
/*
* Find the trigger to delete.
*/
ScanKeyInit(&skey[0],
Anum_pg_trigger_oid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(trigOid));
tgscan = systable_beginscan(tgrel, TriggerOidIndexId, true,
NULL, 1, skey);
tup = systable_getnext(tgscan);
if (!HeapTupleIsValid(tup))
elog(ERROR, "could not find tuple for trigger %u", trigOid);
/*
* Open and exclusive-lock the relation the trigger belongs to.
*/
relid = ((Form_pg_trigger) GETSTRUCT(tup))->tgrelid;
rel = table_open(relid, AccessExclusiveLock);
if (rel->rd_rel->relkind != RELKIND_RELATION &&
rel->rd_rel->relkind != RELKIND_VIEW &&
rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a table, view, or foreign table",
RelationGetRelationName(rel))));
if (!allowSystemTableMods && IsSystemRelation(rel))
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied: \"%s\" is a system catalog",
RelationGetRelationName(rel))));
/*
* Delete the pg_trigger tuple.
*/
CatalogTupleDelete(tgrel, &tup->t_self);
systable_endscan(tgscan);
table_close(tgrel, RowExclusiveLock);
/*
* We do not bother to try to determine whether any other triggers remain,
* which would be needed in order to decide whether it's safe to clear the
* relation's relhastriggers. (In any case, there might be a concurrent
* process adding new triggers.) Instead, just force a relcache inval to
* make other backends (and this one too!) rebuild their relcache entries.
* There's no great harm in leaving relhastriggers true even if there are
* no triggers left.
*/
CacheInvalidateRelcache(rel);
/* Keep lock on trigger's rel until end of xact */
table_close(rel, NoLock);
}
/*
* get_trigger_oid - Look up a trigger by name to find its OID.
*
* If missing_ok is false, throw an error if trigger not found. If
* true, just return InvalidOid.
*/
Oid
get_trigger_oid(Oid relid, const char *trigname, bool missing_ok)
{
Relation tgrel;
ScanKeyData skey[2];
SysScanDesc tgscan;
HeapTuple tup;
Oid oid;
/*
* Find the trigger, verify permissions, set up object address
*/
tgrel = table_open(TriggerRelationId, AccessShareLock);
ScanKeyInit(&skey[0],
Anum_pg_trigger_tgrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
ScanKeyInit(&skey[1],
Anum_pg_trigger_tgname,
BTEqualStrategyNumber, F_NAMEEQ,
CStringGetDatum(trigname));
tgscan = systable_beginscan(tgrel, TriggerRelidNameIndexId, true,
NULL, 2, skey);
tup = systable_getnext(tgscan);
if (!HeapTupleIsValid(tup))
{
if (!missing_ok)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("trigger \"%s\" for table \"%s\" does not exist",
trigname, get_rel_name(relid))));
oid = InvalidOid;
}
else
{
oid = ((Form_pg_trigger) GETSTRUCT(tup))->oid;
}
systable_endscan(tgscan);
table_close(tgrel, AccessShareLock);
return oid;
}
/*
* Perform permissions and integrity checks before acquiring a relation lock.
*/
static void
RangeVarCallbackForRenameTrigger(const RangeVar *rv, Oid relid, Oid oldrelid,
void *arg)
{
HeapTuple tuple;
Form_pg_class form;
tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
if (!HeapTupleIsValid(tuple))
return; /* concurrently dropped */
form = (Form_pg_class) GETSTRUCT(tuple);
/* only tables and views can have triggers */
if (form->relkind != RELKIND_RELATION && form->relkind != RELKIND_VIEW &&
form->relkind != RELKIND_FOREIGN_TABLE &&
form->relkind != RELKIND_PARTITIONED_TABLE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a table, view, or foreign table",
rv->relname)));
/* you must own the table to rename one of its triggers */
if (!pg_class_ownercheck(relid, GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(get_rel_relkind(relid)), rv->relname);
if (!allowSystemTableMods && IsSystemClass(relid, form))
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied: \"%s\" is a system catalog",
rv->relname)));
ReleaseSysCache(tuple);
}
/*
* renametrig - changes the name of a trigger on a relation
*
* trigger name is changed in trigger catalog.
* No record of the previous name is kept.
*
* get proper relrelation from relation catalog (if not arg)
* scan trigger catalog
* for name conflict (within rel)
* for original trigger (if not arg)
* modify tgname in trigger tuple
* update row in catalog
*/
ObjectAddress
renametrig(RenameStmt *stmt)
{
Oid tgoid;
Relation targetrel;
Relation tgrel;
HeapTuple tuple;
SysScanDesc tgscan;
ScanKeyData key[2];
Oid relid;
ObjectAddress address;
/*
* Look up name, check permissions, and acquire lock (which we will NOT
* release until end of transaction).
*/
relid = RangeVarGetRelidExtended(stmt->relation, AccessExclusiveLock,
0,
RangeVarCallbackForRenameTrigger,
NULL);
/* Have lock already, so just need to build relcache entry. */
targetrel = relation_open(relid, NoLock);
/*
* Scan pg_trigger twice for existing triggers on relation. We do this in
* order to ensure a trigger does not exist with newname (The unique index
* on tgrelid/tgname would complain anyway) and to ensure a trigger does
* exist with oldname.
*
* NOTE that this is cool only because we have AccessExclusiveLock on the
* relation, so the trigger set won't be changing underneath us.
*/
tgrel = table_open(TriggerRelationId, RowExclusiveLock);
/*
* First pass -- look for name conflict
*/
ScanKeyInit(&key[0],
Anum_pg_trigger_tgrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
ScanKeyInit(&key[1],
Anum_pg_trigger_tgname,
BTEqualStrategyNumber, F_NAMEEQ,
PointerGetDatum(stmt->newname));
tgscan = systable_beginscan(tgrel, TriggerRelidNameIndexId, true,
NULL, 2, key);
if (HeapTupleIsValid(tuple = systable_getnext(tgscan)))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("trigger \"%s\" for relation \"%s\" already exists",
stmt->newname, RelationGetRelationName(targetrel))));
systable_endscan(tgscan);
/*
* Second pass -- look for trigger existing with oldname and update
*/
ScanKeyInit(&key[0],
Anum_pg_trigger_tgrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
ScanKeyInit(&key[1],
Anum_pg_trigger_tgname,
BTEqualStrategyNumber, F_NAMEEQ,
PointerGetDatum(stmt->subname));
tgscan = systable_beginscan(tgrel, TriggerRelidNameIndexId, true,
NULL, 2, key);
if (HeapTupleIsValid(tuple = systable_getnext(tgscan)))
{
Form_pg_trigger trigform;
/*
* Update pg_trigger tuple with new tgname.
*/
tuple = heap_copytuple(tuple); /* need a modifiable copy */
trigform = (Form_pg_trigger) GETSTRUCT(tuple);
tgoid = trigform->oid;
namestrcpy(&trigform->tgname,
stmt->newname);
CatalogTupleUpdate(tgrel, &tuple->t_self, tuple);
InvokeObjectPostAlterHook(TriggerRelationId,
tgoid, 0);
/*
* Invalidate relation's relcache entry so that other backends (and
* this one too!) are sent SI message to make them rebuild relcache
* entries. (Ideally this should happen automatically...)
*/
CacheInvalidateRelcache(targetrel);
}
else
{
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("trigger \"%s\" for table \"%s\" does not exist",
stmt->subname, RelationGetRelationName(targetrel))));
}
ObjectAddressSet(address, TriggerRelationId, tgoid);
systable_endscan(tgscan);
table_close(tgrel, RowExclusiveLock);
/*
* Close rel, but keep exclusive lock!
*/
relation_close(targetrel, NoLock);
return address;
}
/*
* EnableDisableTrigger()
*
* Called by ALTER TABLE ENABLE/DISABLE [ REPLICA | ALWAYS ] TRIGGER
* to change 'tgenabled' field for the specified trigger(s)
*
* rel: relation to process (caller must hold suitable lock on it)
* tgname: trigger to process, or NULL to scan all triggers
* fires_when: new value for tgenabled field. In addition to generic
* enablement/disablement, this also defines when the trigger
* should be fired in session replication roles.
* skip_system: if true, skip "system" triggers (constraint triggers)
*
* Caller should have checked permissions for the table; here we also
* enforce that superuser privilege is required to alter the state of
* system triggers
*/
void
EnableDisableTrigger(Relation rel, const char *tgname,
char fires_when, bool skip_system, LOCKMODE lockmode)
{
Relation tgrel;
int nkeys;
ScanKeyData keys[2];
SysScanDesc tgscan;
HeapTuple tuple;
bool found;
bool changed;
/* Scan the relevant entries in pg_triggers */
tgrel = table_open(TriggerRelationId, RowExclusiveLock);
ScanKeyInit(&keys[0],
Anum_pg_trigger_tgrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(rel)));
if (tgname)
{
ScanKeyInit(&keys[1],
Anum_pg_trigger_tgname,
BTEqualStrategyNumber, F_NAMEEQ,
CStringGetDatum(tgname));
nkeys = 2;
}
else
nkeys = 1;
tgscan = systable_beginscan(tgrel, TriggerRelidNameIndexId, true,
NULL, nkeys, keys);
found = changed = false;
while (HeapTupleIsValid(tuple = systable_getnext(tgscan)))
{
Form_pg_trigger oldtrig = (Form_pg_trigger) GETSTRUCT(tuple);
if (oldtrig->tgisinternal)
{
/* system trigger ... ok to process? */
if (skip_system)
continue;
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied: \"%s\" is a system trigger",
NameStr(oldtrig->tgname))));
}
found = true;
if (oldtrig->tgenabled != fires_when)
{
/* need to change this one ... make a copy to scribble on */
HeapTuple newtup = heap_copytuple(tuple);
Form_pg_trigger newtrig = (Form_pg_trigger) GETSTRUCT(newtup);
newtrig->tgenabled = fires_when;
CatalogTupleUpdate(tgrel, &newtup->t_self, newtup);
heap_freetuple(newtup);
/*
* When altering FOR EACH ROW triggers on a partitioned table, do
* the same on the partitions as well.
*/
if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE &&
(TRIGGER_FOR_ROW(oldtrig->tgtype)))
{
PartitionDesc partdesc = RelationGetPartitionDesc(rel);
int i;
for (i = 0; i < partdesc->nparts; i++)
{
Relation part;
part = relation_open(partdesc->oids[i], lockmode);
EnableDisableTrigger(part, NameStr(oldtrig->tgname),
fires_when, skip_system, lockmode);
table_close(part, NoLock); /* keep lock till commit */
}
}
changed = true;
}
InvokeObjectPostAlterHook(TriggerRelationId,
oldtrig->oid, 0);
}
systable_endscan(tgscan);
table_close(tgrel, RowExclusiveLock);
if (tgname && !found)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("trigger \"%s\" for table \"%s\" does not exist",
tgname, RelationGetRelationName(rel))));
/*
* If we changed anything, broadcast a SI inval message to force each
* backend (including our own!) to rebuild relation's relcache entry.
* Otherwise they will fail to apply the change promptly.
*/
if (changed)
CacheInvalidateRelcache(rel);
}
/*
* Build trigger data to attach to the given relcache entry.
*
* Note that trigger data attached to a relcache entry must be stored in
* CacheMemoryContext to ensure it survives as long as the relcache entry.
* But we should be running in a less long-lived working context. To avoid
* leaking cache memory if this routine fails partway through, we build a
* temporary TriggerDesc in working memory and then copy the completed
* structure into cache memory.
*/
void
RelationBuildTriggers(Relation relation)
{
TriggerDesc *trigdesc;
int numtrigs;
int maxtrigs;
Trigger *triggers;
Relation tgrel;
ScanKeyData skey;
SysScanDesc tgscan;
HeapTuple htup;
MemoryContext oldContext;
int i;
/*
* Allocate a working array to hold the triggers (the array is extended if
* necessary)
*/
maxtrigs = 16;
triggers = (Trigger *) palloc(maxtrigs * sizeof(Trigger));
numtrigs = 0;
/*
* Note: since we scan the triggers using TriggerRelidNameIndexId, we will
* be reading the triggers in name order, except possibly during
* emergency-recovery operations (ie, IgnoreSystemIndexes). This in turn
* ensures that triggers will be fired in name order.
*/
ScanKeyInit(&skey,
Anum_pg_trigger_tgrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(relation)));
tgrel = table_open(TriggerRelationId, AccessShareLock);
tgscan = systable_beginscan(tgrel, TriggerRelidNameIndexId, true,
NULL, 1, &skey);
while (HeapTupleIsValid(htup = systable_getnext(tgscan)))
{
Form_pg_trigger pg_trigger = (Form_pg_trigger) GETSTRUCT(htup);
Trigger *build;
Datum datum;
bool isnull;
if (numtrigs >= maxtrigs)
{
maxtrigs *= 2;
triggers = (Trigger *) repalloc(triggers, maxtrigs * sizeof(Trigger));
}
build = &(triggers[numtrigs]);
build->tgoid = pg_trigger->oid;
build->tgname = DatumGetCString(DirectFunctionCall1(nameout,
NameGetDatum(&pg_trigger->tgname)));
build->tgfoid = pg_trigger->tgfoid;
build->tgtype = pg_trigger->tgtype;
build->tgenabled = pg_trigger->tgenabled;
build->tgisinternal = pg_trigger->tgisinternal;
build->tgconstrrelid = pg_trigger->tgconstrrelid;
build->tgconstrindid = pg_trigger->tgconstrindid;
build->tgconstraint = pg_trigger->tgconstraint;
build->tgdeferrable = pg_trigger->tgdeferrable;
build->tginitdeferred = pg_trigger->tginitdeferred;
build->tgnargs = pg_trigger->tgnargs;
/* tgattr is first var-width field, so OK to access directly */
build->tgnattr = pg_trigger->tgattr.dim1;
if (build->tgnattr > 0)
{
build->tgattr = (int16 *) palloc(build->tgnattr * sizeof(int16));
memcpy(build->tgattr, &(pg_trigger->tgattr.values),
build->tgnattr * sizeof(int16));
}
else
build->tgattr = NULL;
if (build->tgnargs > 0)
{
bytea *val;
char *p;
val = DatumGetByteaPP(fastgetattr(htup,
Anum_pg_trigger_tgargs,
tgrel->rd_att, &isnull));
if (isnull)
elog(ERROR, "tgargs is null in trigger for relation \"%s\"",
RelationGetRelationName(relation));
p = (char *) VARDATA_ANY(val);
build->tgargs = (char **) palloc(build->tgnargs * sizeof(char *));
for (i = 0; i < build->tgnargs; i++)
{
build->tgargs[i] = pstrdup(p);
p += strlen(p) + 1;
}
}
else
build->tgargs = NULL;
datum = fastgetattr(htup, Anum_pg_trigger_tgoldtable,
tgrel->rd_att, &isnull);
if (!isnull)
build->tgoldtable =
DatumGetCString(DirectFunctionCall1(nameout, datum));
else
build->tgoldtable = NULL;
datum = fastgetattr(htup, Anum_pg_trigger_tgnewtable,
tgrel->rd_att, &isnull);
if (!isnull)
build->tgnewtable =
DatumGetCString(DirectFunctionCall1(nameout, datum));
else
build->tgnewtable = NULL;
datum = fastgetattr(htup, Anum_pg_trigger_tgqual,
tgrel->rd_att, &isnull);
if (!isnull)
build->tgqual = TextDatumGetCString(datum);
else
build->tgqual = NULL;
numtrigs++;
}
systable_endscan(tgscan);
table_close(tgrel, AccessShareLock);
/* There might not be any triggers */
if (numtrigs == 0)
{
pfree(triggers);
return;
}
/* Build trigdesc */
trigdesc = (TriggerDesc *) palloc0(sizeof(TriggerDesc));
trigdesc->triggers = triggers;
trigdesc->numtriggers = numtrigs;
for (i = 0; i < numtrigs; i++)
SetTriggerFlags(trigdesc, &(triggers[i]));
/* Copy completed trigdesc into cache storage */
oldContext = MemoryContextSwitchTo(CacheMemoryContext);
relation->trigdesc = CopyTriggerDesc(trigdesc);
MemoryContextSwitchTo(oldContext);
/* Release working memory */
FreeTriggerDesc(trigdesc);
}
/*
* Update the TriggerDesc's hint flags to include the specified trigger
*/
static void
SetTriggerFlags(TriggerDesc *trigdesc, Trigger *trigger)
{
int16 tgtype = trigger->tgtype;
trigdesc->trig_insert_before_row |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_ROW,
TRIGGER_TYPE_BEFORE, TRIGGER_TYPE_INSERT);
trigdesc->trig_insert_after_row |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_ROW,
TRIGGER_TYPE_AFTER, TRIGGER_TYPE_INSERT);
trigdesc->trig_insert_instead_row |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_ROW,
TRIGGER_TYPE_INSTEAD, TRIGGER_TYPE_INSERT);
trigdesc->trig_insert_before_statement |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_STATEMENT,
TRIGGER_TYPE_BEFORE, TRIGGER_TYPE_INSERT);
trigdesc->trig_insert_after_statement |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_STATEMENT,
TRIGGER_TYPE_AFTER, TRIGGER_TYPE_INSERT);
trigdesc->trig_update_before_row |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_ROW,
TRIGGER_TYPE_BEFORE, TRIGGER_TYPE_UPDATE);
trigdesc->trig_update_after_row |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_ROW,
TRIGGER_TYPE_AFTER, TRIGGER_TYPE_UPDATE);
trigdesc->trig_update_instead_row |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_ROW,
TRIGGER_TYPE_INSTEAD, TRIGGER_TYPE_UPDATE);
trigdesc->trig_update_before_statement |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_STATEMENT,
TRIGGER_TYPE_BEFORE, TRIGGER_TYPE_UPDATE);
trigdesc->trig_update_after_statement |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_STATEMENT,
TRIGGER_TYPE_AFTER, TRIGGER_TYPE_UPDATE);
trigdesc->trig_delete_before_row |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_ROW,
TRIGGER_TYPE_BEFORE, TRIGGER_TYPE_DELETE);
trigdesc->trig_delete_after_row |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_ROW,
TRIGGER_TYPE_AFTER, TRIGGER_TYPE_DELETE);
trigdesc->trig_delete_instead_row |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_ROW,
TRIGGER_TYPE_INSTEAD, TRIGGER_TYPE_DELETE);
trigdesc->trig_delete_before_statement |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_STATEMENT,
TRIGGER_TYPE_BEFORE, TRIGGER_TYPE_DELETE);
trigdesc->trig_delete_after_statement |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_STATEMENT,
TRIGGER_TYPE_AFTER, TRIGGER_TYPE_DELETE);
/* there are no row-level truncate triggers */
trigdesc->trig_truncate_before_statement |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_STATEMENT,
TRIGGER_TYPE_BEFORE, TRIGGER_TYPE_TRUNCATE);
trigdesc->trig_truncate_after_statement |=
TRIGGER_TYPE_MATCHES(tgtype, TRIGGER_TYPE_STATEMENT,
TRIGGER_TYPE_AFTER, TRIGGER_TYPE_TRUNCATE);
trigdesc->trig_insert_new_table |=
(TRIGGER_FOR_INSERT(tgtype) &&
TRIGGER_USES_TRANSITION_TABLE(trigger->tgnewtable));
trigdesc->trig_update_old_table |=
(TRIGGER_FOR_UPDATE(tgtype) &&
TRIGGER_USES_TRANSITION_TABLE(trigger->tgoldtable));
trigdesc->trig_update_new_table |=
(TRIGGER_FOR_UPDATE(tgtype) &&
TRIGGER_USES_TRANSITION_TABLE(trigger->tgnewtable));
trigdesc->trig_delete_old_table |=
(TRIGGER_FOR_DELETE(tgtype) &&
TRIGGER_USES_TRANSITION_TABLE(trigger->tgoldtable));
}
/*
* Copy a TriggerDesc data structure.
*
* The copy is allocated in the current memory context.
*/
TriggerDesc *
CopyTriggerDesc(TriggerDesc *trigdesc)
{
TriggerDesc *newdesc;
Trigger *trigger;
int i;
if (trigdesc == NULL || trigdesc->numtriggers <= 0)
return NULL;
newdesc = (TriggerDesc *) palloc(sizeof(TriggerDesc));
memcpy(newdesc, trigdesc, sizeof(TriggerDesc));
trigger = (Trigger *) palloc(trigdesc->numtriggers * sizeof(Trigger));
memcpy(trigger, trigdesc->triggers,
trigdesc->numtriggers * sizeof(Trigger));
newdesc->triggers = trigger;
for (i = 0; i < trigdesc->numtriggers; i++)
{
trigger->tgname = pstrdup(trigger->tgname);
if (trigger->tgnattr > 0)
{
int16 *newattr;
newattr = (int16 *) palloc(trigger->tgnattr * sizeof(int16));
memcpy(newattr, trigger->tgattr,
trigger->tgnattr * sizeof(int16));
trigger->tgattr = newattr;
}
if (trigger->tgnargs > 0)
{
char **newargs;
int16 j;
newargs = (char **) palloc(trigger->tgnargs * sizeof(char *));
for (j = 0; j < trigger->tgnargs; j++)
newargs[j] = pstrdup(trigger->tgargs[j]);
trigger->tgargs = newargs;
}
if (trigger->tgqual)
trigger->tgqual = pstrdup(trigger->tgqual);
if (trigger->tgoldtable)
trigger->tgoldtable = pstrdup(trigger->tgoldtable);
if (trigger->tgnewtable)
trigger->tgnewtable = pstrdup(trigger->tgnewtable);
trigger++;
}
return newdesc;
}
/*
* Free a TriggerDesc data structure.
*/
void
FreeTriggerDesc(TriggerDesc *trigdesc)
{
Trigger *trigger;
int i;
if (trigdesc == NULL)
return;
trigger = trigdesc->triggers;
for (i = 0; i < trigdesc->numtriggers; i++)
{
pfree(trigger->tgname);
if (trigger->tgnattr > 0)
pfree(trigger->tgattr);
if (trigger->tgnargs > 0)
{
while (--(trigger->tgnargs) >= 0)
pfree(trigger->tgargs[trigger->tgnargs]);
pfree(trigger->tgargs);
}
if (trigger->tgqual)
pfree(trigger->tgqual);
if (trigger->tgoldtable)
pfree(trigger->tgoldtable);
if (trigger->tgnewtable)
pfree(trigger->tgnewtable);
trigger++;
}
pfree(trigdesc->triggers);
pfree(trigdesc);
}
/*
* Compare two TriggerDesc structures for logical equality.
*/
#ifdef NOT_USED
bool
equalTriggerDescs(TriggerDesc *trigdesc1, TriggerDesc *trigdesc2)
{
int i,
j;
/*
* We need not examine the hint flags, just the trigger array itself; if
* we have the same triggers with the same types, the flags should match.
*
* As of 7.3 we assume trigger set ordering is significant in the
* comparison; so we just compare corresponding slots of the two sets.
*
* Note: comparing the stringToNode forms of the WHEN clauses means that
* parse column locations will affect the result. This is okay as long as
* this function is only used for detecting exact equality, as for example
* in checking for staleness of a cache entry.
*/
if (trigdesc1 != NULL)
{
if (trigdesc2 == NULL)
return false;
if (trigdesc1->numtriggers != trigdesc2->numtriggers)
return false;
for (i = 0; i < trigdesc1->numtriggers; i++)
{
Trigger *trig1 = trigdesc1->triggers + i;
Trigger *trig2 = trigdesc2->triggers + i;
if (trig1->tgoid != trig2->tgoid)
return false;
if (strcmp(trig1->tgname, trig2->tgname) != 0)
return false;
if (trig1->tgfoid != trig2->tgfoid)
return false;
if (trig1->tgtype != trig2->tgtype)
return false;
if (trig1->tgenabled != trig2->tgenabled)
return false;
if (trig1->tgisinternal != trig2->tgisinternal)
return false;
if (trig1->tgconstrrelid != trig2->tgconstrrelid)
return false;
if (trig1->tgconstrindid != trig2->tgconstrindid)
return false;
if (trig1->tgconstraint != trig2->tgconstraint)
return false;
if (trig1->tgdeferrable != trig2->tgdeferrable)
return false;
if (trig1->tginitdeferred != trig2->tginitdeferred)
return false;
if (trig1->tgnargs != trig2->tgnargs)
return false;
if (trig1->tgnattr != trig2->tgnattr)
return false;
if (trig1->tgnattr > 0 &&
memcmp(trig1->tgattr, trig2->tgattr,
trig1->tgnattr * sizeof(int16)) != 0)
return false;
for (j = 0; j < trig1->tgnargs; j++)
if (strcmp(trig1->tgargs[j], trig2->tgargs[j]) != 0)
return false;
if (trig1->tgqual == NULL && trig2->tgqual == NULL)
/* ok */ ;
else if (trig1->tgqual == NULL || trig2->tgqual == NULL)
return false;
else if (strcmp(trig1->tgqual, trig2->tgqual) != 0)
return false;
if (trig1->tgoldtable == NULL && trig2->tgoldtable == NULL)
/* ok */ ;
else if (trig1->tgoldtable == NULL || trig2->tgoldtable == NULL)
return false;
else if (strcmp(trig1->tgoldtable, trig2->tgoldtable) != 0)
return false;
if (trig1->tgnewtable == NULL && trig2->tgnewtable == NULL)
/* ok */ ;
else if (trig1->tgnewtable == NULL || trig2->tgnewtable == NULL)
return false;
else if (strcmp(trig1->tgnewtable, trig2->tgnewtable) != 0)
return false;
}
}
else if (trigdesc2 != NULL)
return false;
return true;
}
#endif /* NOT_USED */
/*
* Check if there is a row-level trigger with transition tables that prevents
* a table from becoming an inheritance child or partition. Return the name
* of the first such incompatible trigger, or NULL if there is none.
*/
const char *
FindTriggerIncompatibleWithInheritance(TriggerDesc *trigdesc)
{
if (trigdesc != NULL)
{
int i;
for (i = 0; i < trigdesc->numtriggers; ++i)
{
Trigger *trigger = &trigdesc->triggers[i];
if (trigger->tgoldtable != NULL || trigger->tgnewtable != NULL)
return trigger->tgname;
}
}
return NULL;
}
/*
* Call a trigger function.
*
* trigdata: trigger descriptor.
* tgindx: trigger's index in finfo and instr arrays.
* finfo: array of cached trigger function call information.
* instr: optional array of EXPLAIN ANALYZE instrumentation state.
* per_tuple_context: memory context to execute the function in.
*
* Returns the tuple (or NULL) as returned by the function.
*/
static HeapTuple
ExecCallTriggerFunc(TriggerData *trigdata,
int tgindx,
FmgrInfo *finfo,
Instrumentation *instr,
MemoryContext per_tuple_context)
{
LOCAL_FCINFO(fcinfo, 0);
PgStat_FunctionCallUsage fcusage;
Datum result;
MemoryContext oldContext;
/*
* Protect against code paths that may fail to initialize transition table
* info.
*/
Assert(((TRIGGER_FIRED_BY_INSERT(trigdata->tg_event) ||
TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event) ||
TRIGGER_FIRED_BY_DELETE(trigdata->tg_event)) &&
TRIGGER_FIRED_AFTER(trigdata->tg_event) &&
!(trigdata->tg_event & AFTER_TRIGGER_DEFERRABLE) &&
!(trigdata->tg_event & AFTER_TRIGGER_INITDEFERRED)) ||
(trigdata->tg_oldtable == NULL && trigdata->tg_newtable == NULL));
finfo += tgindx;
/*
* We cache fmgr lookup info, to avoid making the lookup again on each
* call.
*/
if (finfo->fn_oid == InvalidOid)
fmgr_info(trigdata->tg_trigger->tgfoid, finfo);
Assert(finfo->fn_oid == trigdata->tg_trigger->tgfoid);
/*
* If doing EXPLAIN ANALYZE, start charging time to this trigger.
*/
if (instr)
InstrStartNode(instr + tgindx);
/*
* Do the function evaluation in the per-tuple memory context, so that
* leaked memory will be reclaimed once per tuple. Note in particular that
* any new tuple created by the trigger function will live till the end of
* the tuple cycle.
*/
oldContext = MemoryContextSwitchTo(per_tuple_context);
/*
* Call the function, passing no arguments but setting a context.
*/
InitFunctionCallInfoData(*fcinfo, finfo, 0,
InvalidOid, (Node *) trigdata, NULL);
pgstat_init_function_usage(fcinfo, &fcusage);
MyTriggerDepth++;
PG_TRY();
{
result = FunctionCallInvoke(fcinfo);
}
PG_CATCH();
{
MyTriggerDepth--;
PG_RE_THROW();
}
PG_END_TRY();
MyTriggerDepth--;
pgstat_end_function_usage(&fcusage, true);
MemoryContextSwitchTo(oldContext);
/*
* Trigger protocol allows function to return a null pointer, but NOT to
* set the isnull result flag.
*/
if (fcinfo->isnull)
ereport(ERROR,
(errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
errmsg("trigger function %u returned null value",
fcinfo->flinfo->fn_oid)));
/*
* If doing EXPLAIN ANALYZE, stop charging time to this trigger, and count
* one "tuple returned" (really the number of firings).
*/
if (instr)
InstrStopNode(instr + tgindx, 1);
return (HeapTuple) DatumGetPointer(result);
}
void
ExecBSInsertTriggers(EState *estate, ResultRelInfo *relinfo)
{
TriggerDesc *trigdesc;
int i;
TriggerData LocTriggerData;
if (Gp_role == GP_ROLE_EXECUTE)
{
/* Don't fire statement-triggers in executor nodes. */
return;
}
trigdesc = relinfo->ri_TrigDesc;
if (trigdesc == NULL)
return;
if (!trigdesc->trig_insert_before_statement)
return;
/* no-op if we already fired BS triggers in this context */
if (before_stmt_triggers_fired(RelationGetRelid(relinfo->ri_RelationDesc),
CMD_INSERT))
return;
LocTriggerData.type = T_TriggerData;
LocTriggerData.tg_event = TRIGGER_EVENT_INSERT |
TRIGGER_EVENT_BEFORE;
LocTriggerData.tg_relation = relinfo->ri_RelationDesc;
LocTriggerData.tg_trigtuple = NULL;
LocTriggerData.tg_newtuple = NULL;
LocTriggerData.tg_trigslot = NULL;
LocTriggerData.tg_newslot = NULL;
LocTriggerData.tg_oldtable = NULL;
LocTriggerData.tg_newtable = NULL;
for (i = 0; i < trigdesc->numtriggers; i++)
{
Trigger *trigger = &trigdesc->triggers[i];
HeapTuple newtuple;
if (!TRIGGER_TYPE_MATCHES(trigger->tgtype,
TRIGGER_TYPE_STATEMENT,
TRIGGER_TYPE_BEFORE,
TRIGGER_TYPE_INSERT))
continue;
if (!TriggerEnabled(estate, relinfo, trigger, LocTriggerData.tg_event,
NULL, NULL, NULL))
continue;
LocTriggerData.tg_trigger = trigger;
newtuple = ExecCallTriggerFunc(&LocTriggerData,
i,
relinfo->ri_TrigFunctions,
relinfo->ri_TrigInstrument,
GetPerTupleMemoryContext(estate));
if (newtuple)
ereport(ERROR,
(errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
errmsg("BEFORE STATEMENT trigger cannot return a value")));
}
}
void
ExecASInsertTriggers(EState *estate, ResultRelInfo *relinfo,
TransitionCaptureState *transition_capture)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
if (trigdesc && trigdesc->trig_insert_after_statement)
AfterTriggerSaveEvent(estate, relinfo, TRIGGER_EVENT_INSERT,
false, NULL, NULL, NIL, NULL, transition_capture);
}
bool
ExecBRInsertTriggers(EState *estate, ResultRelInfo *relinfo,
TupleTableSlot *slot)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
HeapTuple newtuple = false;
bool should_free;
TriggerData LocTriggerData;
int i;
LocTriggerData.type = T_TriggerData;
LocTriggerData.tg_event = TRIGGER_EVENT_INSERT |
TRIGGER_EVENT_ROW |
TRIGGER_EVENT_BEFORE;
LocTriggerData.tg_relation = relinfo->ri_RelationDesc;
LocTriggerData.tg_trigtuple = NULL;
LocTriggerData.tg_newtuple = NULL;
LocTriggerData.tg_trigslot = NULL;
LocTriggerData.tg_newslot = NULL;
LocTriggerData.tg_oldtable = NULL;
LocTriggerData.tg_newtable = NULL;
for (i = 0; i < trigdesc->numtriggers; i++)
{
Trigger *trigger = &trigdesc->triggers[i];
HeapTuple oldtuple;
if (!TRIGGER_TYPE_MATCHES(trigger->tgtype,
TRIGGER_TYPE_ROW,
TRIGGER_TYPE_BEFORE,
TRIGGER_TYPE_INSERT))
continue;
if (!TriggerEnabled(estate, relinfo, trigger, LocTriggerData.tg_event,
NULL, NULL, slot))
continue;
if (!newtuple)
newtuple = ExecFetchSlotHeapTuple(slot, true, &should_free);
LocTriggerData.tg_trigslot = slot;
LocTriggerData.tg_trigtuple = oldtuple = newtuple;
LocTriggerData.tg_trigger = trigger;
newtuple = ExecCallTriggerFunc(&LocTriggerData,
i,
relinfo->ri_TrigFunctions,
relinfo->ri_TrigInstrument,
GetPerTupleMemoryContext(estate));
if (newtuple == NULL)
{
if (should_free)
heap_freetuple(oldtuple);
return false; /* "do nothing" */
}
else if (newtuple != oldtuple)
{
ExecForceStoreHeapTuple(newtuple, slot, false);
if (should_free)
heap_freetuple(oldtuple);
/* signal tuple should be re-fetched if used */
newtuple = NULL;
}
}
return true;
}
void
ExecARInsertTriggers(EState *estate, ResultRelInfo *relinfo,
TupleTableSlot *slot, List *recheckIndexes,
TransitionCaptureState *transition_capture)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
if ((trigdesc && trigdesc->trig_insert_after_row) ||
(transition_capture && transition_capture->tcs_insert_new_table))
{
if(RelationIsAoCols(relinfo->ri_RelationDesc))
elog(ERROR, "Trigger is not supported on AOCS yet");
AfterTriggerSaveEvent(estate, relinfo, TRIGGER_EVENT_INSERT,
true, NULL, slot,
recheckIndexes, NULL,
transition_capture);
}
}
bool
ExecIRInsertTriggers(EState *estate, ResultRelInfo *relinfo,
TupleTableSlot *slot)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
HeapTuple newtuple = NULL;
bool should_free;
TriggerData LocTriggerData;
int i;
LocTriggerData.type = T_TriggerData;
LocTriggerData.tg_event = TRIGGER_EVENT_INSERT |
TRIGGER_EVENT_ROW |
TRIGGER_EVENT_INSTEAD;
LocTriggerData.tg_relation = relinfo->ri_RelationDesc;
LocTriggerData.tg_trigtuple = NULL;
LocTriggerData.tg_newtuple = NULL;
LocTriggerData.tg_trigslot = NULL;
LocTriggerData.tg_newslot = NULL;
LocTriggerData.tg_oldtable = NULL;
LocTriggerData.tg_newtable = NULL;
for (i = 0; i < trigdesc->numtriggers; i++)
{
Trigger *trigger = &trigdesc->triggers[i];
HeapTuple oldtuple;
if (!TRIGGER_TYPE_MATCHES(trigger->tgtype,
TRIGGER_TYPE_ROW,
TRIGGER_TYPE_INSTEAD,
TRIGGER_TYPE_INSERT))
continue;
if (!TriggerEnabled(estate, relinfo, trigger, LocTriggerData.tg_event,
NULL, NULL, slot))
continue;
if (!newtuple)
newtuple = ExecFetchSlotHeapTuple(slot, true, &should_free);
LocTriggerData.tg_trigslot = slot;
LocTriggerData.tg_trigtuple = oldtuple = newtuple;
LocTriggerData.tg_trigger = trigger;
newtuple = ExecCallTriggerFunc(&LocTriggerData,
i,
relinfo->ri_TrigFunctions,
relinfo->ri_TrigInstrument,
GetPerTupleMemoryContext(estate));
if (newtuple == NULL)
{
if (should_free)
heap_freetuple(oldtuple);
return false; /* "do nothing" */
}
else if (newtuple != oldtuple)
{
ExecForceStoreHeapTuple(newtuple, slot, false);
if (should_free)
heap_freetuple(oldtuple);
/* signal tuple should be re-fetched if used */
newtuple = NULL;
}
}
return true;
}
void
ExecBSDeleteTriggers(EState *estate, ResultRelInfo *relinfo)
{
TriggerDesc *trigdesc;
int i;
TriggerData LocTriggerData;
if (Gp_role == GP_ROLE_EXECUTE)
{
/* Don't fire statement-triggers in executor nodes. */
return;
}
trigdesc = relinfo->ri_TrigDesc;
if (trigdesc == NULL)
return;
if (!trigdesc->trig_delete_before_statement)
return;
/* no-op if we already fired BS triggers in this context */
if (before_stmt_triggers_fired(RelationGetRelid(relinfo->ri_RelationDesc),
CMD_DELETE))
return;
LocTriggerData.type = T_TriggerData;
LocTriggerData.tg_event = TRIGGER_EVENT_DELETE |
TRIGGER_EVENT_BEFORE;
LocTriggerData.tg_relation = relinfo->ri_RelationDesc;
LocTriggerData.tg_trigtuple = NULL;
LocTriggerData.tg_newtuple = NULL;
LocTriggerData.tg_trigslot = NULL;
LocTriggerData.tg_newslot = NULL;
LocTriggerData.tg_oldtable = NULL;
LocTriggerData.tg_newtable = NULL;
for (i = 0; i < trigdesc->numtriggers; i++)
{
Trigger *trigger = &trigdesc->triggers[i];
HeapTuple newtuple;
if (!TRIGGER_TYPE_MATCHES(trigger->tgtype,
TRIGGER_TYPE_STATEMENT,
TRIGGER_TYPE_BEFORE,
TRIGGER_TYPE_DELETE))
continue;
if (!TriggerEnabled(estate, relinfo, trigger, LocTriggerData.tg_event,
NULL, NULL, NULL))
continue;
LocTriggerData.tg_trigger = trigger;
newtuple = ExecCallTriggerFunc(&LocTriggerData,
i,
relinfo->ri_TrigFunctions,
relinfo->ri_TrigInstrument,
GetPerTupleMemoryContext(estate));
if (newtuple)
ereport(ERROR,
(errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
errmsg("BEFORE STATEMENT trigger cannot return a value")));
}
}
void
ExecASDeleteTriggers(EState *estate, ResultRelInfo *relinfo,
TransitionCaptureState *transition_capture)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
if (trigdesc && trigdesc->trig_delete_after_statement)
AfterTriggerSaveEvent(estate, relinfo, TRIGGER_EVENT_DELETE,
false, NULL, NULL, NIL, NULL, transition_capture);
}
/*
* Execute BEFORE ROW DELETE triggers.
*
* True indicates caller can proceed with the delete. False indicates caller
* need to suppress the delete and additionally if requested, we need to pass
* back the concurrently updated tuple if any.
*/
bool
ExecBRDeleteTriggers(EState *estate, EPQState *epqstate,
ResultRelInfo *relinfo,
ItemPointer tupleid,
HeapTuple fdw_trigtuple,
TupleTableSlot **epqslot)
{
TupleTableSlot *slot = ExecGetTriggerOldSlot(estate, relinfo);
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
bool result = true;
TriggerData LocTriggerData;
HeapTuple trigtuple;
bool should_free = false;
int i;
Assert(HeapTupleIsValid(fdw_trigtuple) ^ ItemPointerIsValid(tupleid));
if (fdw_trigtuple == NULL)
{
TupleTableSlot *newSlot;
if (!GetTupleForTrigger(estate, epqstate, relinfo, tupleid,
LockTupleExclusive, slot, &newSlot))
return false;
/*
* If the tuple was concurrently updated and the caller of this
* function requested for the updated tuple, skip the trigger
* execution.
*/
if (newSlot != NULL && epqslot != NULL)
{
*epqslot = newSlot;
return false;
}
trigtuple = ExecFetchSlotHeapTuple(slot, true, &should_free);
}
else
{
trigtuple = fdw_trigtuple;
ExecForceStoreHeapTuple(trigtuple, slot, false);
}
LocTriggerData.type = T_TriggerData;
LocTriggerData.tg_event = TRIGGER_EVENT_DELETE |
TRIGGER_EVENT_ROW |
TRIGGER_EVENT_BEFORE;
LocTriggerData.tg_relation = relinfo->ri_RelationDesc;
LocTriggerData.tg_trigtuple = NULL;
LocTriggerData.tg_newtuple = NULL;
LocTriggerData.tg_trigslot = NULL;
LocTriggerData.tg_newslot = NULL;
LocTriggerData.tg_oldtable = NULL;
LocTriggerData.tg_newtable = NULL;
for (i = 0; i < trigdesc->numtriggers; i++)
{
HeapTuple newtuple;
Trigger *trigger = &trigdesc->triggers[i];
if (!TRIGGER_TYPE_MATCHES(trigger->tgtype,
TRIGGER_TYPE_ROW,
TRIGGER_TYPE_BEFORE,
TRIGGER_TYPE_DELETE))
continue;
if (!TriggerEnabled(estate, relinfo, trigger, LocTriggerData.tg_event,
NULL, slot, NULL))
continue;
LocTriggerData.tg_trigslot = slot;
LocTriggerData.tg_trigtuple = trigtuple;
LocTriggerData.tg_trigger = trigger;
newtuple = ExecCallTriggerFunc(&LocTriggerData,
i,
relinfo->ri_TrigFunctions,
relinfo->ri_TrigInstrument,
GetPerTupleMemoryContext(estate));
if (newtuple == NULL)
{
result = false; /* tell caller to suppress delete */
break;
}
if (newtuple != trigtuple)
heap_freetuple(newtuple);
}
if (should_free)
heap_freetuple(trigtuple);
return result;
}
void
ExecARDeleteTriggers(EState *estate, ResultRelInfo *relinfo,
ItemPointer tupleid,
HeapTuple fdw_trigtuple,
TransitionCaptureState *transition_capture)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
TupleTableSlot *slot = ExecGetTriggerOldSlot(estate, relinfo);
if ((trigdesc && trigdesc->trig_delete_after_row) ||
(transition_capture && transition_capture->tcs_delete_old_table))
{
Assert(HeapTupleIsValid(fdw_trigtuple) ^ ItemPointerIsValid(tupleid));
if (fdw_trigtuple == NULL)
GetTupleForTrigger(estate,
NULL,
relinfo,
tupleid,
LockTupleExclusive,
slot,
NULL);
else
ExecForceStoreHeapTuple(fdw_trigtuple, slot, false);
AfterTriggerSaveEvent(estate, relinfo, TRIGGER_EVENT_DELETE,
true, slot, NULL, NIL, NULL,
transition_capture);
}
}
bool
ExecIRDeleteTriggers(EState *estate, ResultRelInfo *relinfo,
HeapTuple trigtuple)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
TupleTableSlot *slot = ExecGetTriggerOldSlot(estate, relinfo);
TriggerData LocTriggerData;
int i;
LocTriggerData.type = T_TriggerData;
LocTriggerData.tg_event = TRIGGER_EVENT_DELETE |
TRIGGER_EVENT_ROW |
TRIGGER_EVENT_INSTEAD;
LocTriggerData.tg_relation = relinfo->ri_RelationDesc;
LocTriggerData.tg_trigtuple = NULL;
LocTriggerData.tg_newtuple = NULL;
LocTriggerData.tg_trigslot = NULL;
LocTriggerData.tg_newslot = NULL;
LocTriggerData.tg_oldtable = NULL;
LocTriggerData.tg_newtable = NULL;
ExecForceStoreHeapTuple(trigtuple, slot, false);
for (i = 0; i < trigdesc->numtriggers; i++)
{
HeapTuple rettuple;
Trigger *trigger = &trigdesc->triggers[i];
if (!TRIGGER_TYPE_MATCHES(trigger->tgtype,
TRIGGER_TYPE_ROW,
TRIGGER_TYPE_INSTEAD,
TRIGGER_TYPE_DELETE))
continue;
if (!TriggerEnabled(estate, relinfo, trigger, LocTriggerData.tg_event,
NULL, slot, NULL))
continue;
LocTriggerData.tg_trigslot = slot;
LocTriggerData.tg_trigtuple = trigtuple;
LocTriggerData.tg_trigger = trigger;
rettuple = ExecCallTriggerFunc(&LocTriggerData,
i,
relinfo->ri_TrigFunctions,
relinfo->ri_TrigInstrument,
GetPerTupleMemoryContext(estate));
if (rettuple == NULL)
return false; /* Delete was suppressed */
if (rettuple != trigtuple)
heap_freetuple(rettuple);
}
return true;
}
void
ExecBSUpdateTriggers(EState *estate, ResultRelInfo *relinfo)
{
TriggerDesc *trigdesc;
int i;
TriggerData LocTriggerData;
Bitmapset *updatedCols;
if (Gp_role == GP_ROLE_EXECUTE)
{
/* Don't fire statement-triggers in executor nodes. */
return;
}
trigdesc = relinfo->ri_TrigDesc;
if (trigdesc == NULL)
return;
if (!trigdesc->trig_update_before_statement)
return;
/* no-op if we already fired BS triggers in this context */
if (before_stmt_triggers_fired(RelationGetRelid(relinfo->ri_RelationDesc),
CMD_UPDATE))
return;
updatedCols = GetAllUpdatedColumns(relinfo, estate);
LocTriggerData.type = T_TriggerData;
LocTriggerData.tg_event = TRIGGER_EVENT_UPDATE |
TRIGGER_EVENT_BEFORE;
LocTriggerData.tg_relation = relinfo->ri_RelationDesc;
LocTriggerData.tg_trigtuple = NULL;
LocTriggerData.tg_newtuple = NULL;
LocTriggerData.tg_trigslot = NULL;
LocTriggerData.tg_newslot = NULL;
LocTriggerData.tg_oldtable = NULL;
LocTriggerData.tg_newtable = NULL;
for (i = 0; i < trigdesc->numtriggers; i++)
{
Trigger *trigger = &trigdesc->triggers[i];
HeapTuple newtuple;
if (!TRIGGER_TYPE_MATCHES(trigger->tgtype,
TRIGGER_TYPE_STATEMENT,
TRIGGER_TYPE_BEFORE,
TRIGGER_TYPE_UPDATE))
continue;
if (!TriggerEnabled(estate, relinfo, trigger, LocTriggerData.tg_event,
updatedCols, NULL, NULL))
continue;
LocTriggerData.tg_trigger = trigger;
newtuple = ExecCallTriggerFunc(&LocTriggerData,
i,
relinfo->ri_TrigFunctions,
relinfo->ri_TrigInstrument,
GetPerTupleMemoryContext(estate));
if (newtuple)
ereport(ERROR,
(errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
errmsg("BEFORE STATEMENT trigger cannot return a value")));
}
}
void
ExecASUpdateTriggers(EState *estate, ResultRelInfo *relinfo,
TransitionCaptureState *transition_capture)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
if (trigdesc && trigdesc->trig_update_after_statement)
AfterTriggerSaveEvent(estate, relinfo, TRIGGER_EVENT_UPDATE,
false, NULL, NULL, NIL,
GetAllUpdatedColumns(relinfo, estate),
transition_capture);
}
bool
ExecBRUpdateTriggers(EState *estate, EPQState *epqstate,
ResultRelInfo *relinfo,
ItemPointer tupleid,
HeapTuple fdw_trigtuple,
TupleTableSlot *newslot)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
TupleTableSlot *oldslot = ExecGetTriggerOldSlot(estate, relinfo);
HeapTuple newtuple = NULL;
HeapTuple trigtuple;
bool should_free_trig = false;
bool should_free_new = false;
TriggerData LocTriggerData;
int i;
Bitmapset *updatedCols;
LockTupleMode lockmode;
/* Determine lock mode to use */
lockmode = ExecUpdateLockMode(estate, relinfo);
Assert(HeapTupleIsValid(fdw_trigtuple) ^ ItemPointerIsValid(tupleid));
if (fdw_trigtuple == NULL)
{
TupleTableSlot *newSlot = NULL;
/* get a copy of the on-disk tuple we are planning to update */
if (!GetTupleForTrigger(estate, epqstate, relinfo, tupleid,
lockmode, oldslot, &newSlot))
return false; /* cancel the update action */
/*
* In READ COMMITTED isolation level it's possible that target tuple
* was changed due to concurrent update. In that case we have a raw
* subplan output tuple in newSlot, and need to run it through the
* junk filter to produce an insertable tuple.
*
* Caution: more than likely, the passed-in slot is the same as the
* junkfilter's output slot, so we are clobbering the original value
* of slottuple by doing the filtering. This is OK since neither we
* nor our caller have any more interest in the prior contents of that
* slot.
*/
if (newSlot != NULL)
{
TupleTableSlot *slot = ExecFilterJunk(relinfo->ri_junkFilter, newSlot);
ExecCopySlot(newslot, slot);
}
trigtuple = ExecFetchSlotHeapTuple(oldslot, true, &should_free_trig);
}
else
{
ExecForceStoreHeapTuple(fdw_trigtuple, oldslot, false);
trigtuple = fdw_trigtuple;
}
LocTriggerData.type = T_TriggerData;
LocTriggerData.tg_event = TRIGGER_EVENT_UPDATE |
TRIGGER_EVENT_ROW |
TRIGGER_EVENT_BEFORE;
LocTriggerData.tg_relation = relinfo->ri_RelationDesc;
LocTriggerData.tg_oldtable = NULL;
LocTriggerData.tg_newtable = NULL;
updatedCols = GetAllUpdatedColumns(relinfo, estate);
for (i = 0; i < trigdesc->numtriggers; i++)
{
Trigger *trigger = &trigdesc->triggers[i];
HeapTuple oldtuple;
if (!TRIGGER_TYPE_MATCHES(trigger->tgtype,
TRIGGER_TYPE_ROW,
TRIGGER_TYPE_BEFORE,
TRIGGER_TYPE_UPDATE))
continue;
if (!TriggerEnabled(estate, relinfo, trigger, LocTriggerData.tg_event,
updatedCols, oldslot, newslot))
continue;
if (!newtuple)
newtuple = ExecFetchSlotHeapTuple(newslot, true, &should_free_new);
LocTriggerData.tg_trigslot = oldslot;
LocTriggerData.tg_trigtuple = trigtuple;
LocTriggerData.tg_newtuple = oldtuple = newtuple;
LocTriggerData.tg_newslot = newslot;
LocTriggerData.tg_trigger = trigger;
newtuple = ExecCallTriggerFunc(&LocTriggerData,
i,
relinfo->ri_TrigFunctions,
relinfo->ri_TrigInstrument,
GetPerTupleMemoryContext(estate));
if (newtuple == NULL)
{
if (should_free_trig)
heap_freetuple(trigtuple);
if (should_free_new)
heap_freetuple(oldtuple);
return false; /* "do nothing" */
}
else if (newtuple != oldtuple)
{
ExecForceStoreHeapTuple(newtuple, newslot, false);
/*
* If the tuple returned by the trigger / being stored, is the old
* row version, and the heap tuple passed to the trigger was
* allocated locally, materialize the slot. Otherwise we might
* free it while still referenced by the slot.
*/
if (should_free_trig && newtuple == trigtuple)
ExecMaterializeSlot(newslot);
if (should_free_new)
heap_freetuple(oldtuple);
/* signal tuple should be re-fetched if used */
newtuple = NULL;
}
}
if (should_free_trig)
heap_freetuple(trigtuple);
return true;
}
void
ExecARUpdateTriggers(EState *estate, ResultRelInfo *relinfo,
ItemPointer tupleid,
HeapTuple fdw_trigtuple,
TupleTableSlot *newslot,
List *recheckIndexes,
TransitionCaptureState *transition_capture)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
TupleTableSlot *oldslot = ExecGetTriggerOldSlot(estate, relinfo);
ExecClearTuple(oldslot);
if ((trigdesc && trigdesc->trig_update_after_row) ||
(transition_capture &&
(transition_capture->tcs_update_old_table ||
transition_capture->tcs_update_new_table)))
{
/*
* Note: if the UPDATE is converted into a DELETE+INSERT as part of
* update-partition-key operation, then this function is also called
* separately for DELETE and INSERT to capture transition table rows.
* In such case, either old tuple or new tuple can be NULL.
*/
if (fdw_trigtuple == NULL && ItemPointerIsValid(tupleid))
GetTupleForTrigger(estate,
NULL,
relinfo,
tupleid,
LockTupleExclusive,
oldslot,
NULL);
else if (fdw_trigtuple != NULL)
ExecForceStoreHeapTuple(fdw_trigtuple, oldslot, false);
AfterTriggerSaveEvent(estate, relinfo, TRIGGER_EVENT_UPDATE,
true, oldslot, newslot, recheckIndexes,
GetAllUpdatedColumns(relinfo, estate),
transition_capture);
}
}
bool
ExecIRUpdateTriggers(EState *estate, ResultRelInfo *relinfo,
HeapTuple trigtuple, TupleTableSlot *newslot)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
TupleTableSlot *oldslot = ExecGetTriggerOldSlot(estate, relinfo);
HeapTuple newtuple = false;
bool should_free;
TriggerData LocTriggerData;
int i;
LocTriggerData.type = T_TriggerData;
LocTriggerData.tg_event = TRIGGER_EVENT_UPDATE |
TRIGGER_EVENT_ROW |
TRIGGER_EVENT_INSTEAD;
LocTriggerData.tg_relation = relinfo->ri_RelationDesc;
LocTriggerData.tg_oldtable = NULL;
LocTriggerData.tg_newtable = NULL;
ExecForceStoreHeapTuple(trigtuple, oldslot, false);
for (i = 0; i < trigdesc->numtriggers; i++)
{
Trigger *trigger = &trigdesc->triggers[i];
HeapTuple oldtuple;
if (!TRIGGER_TYPE_MATCHES(trigger->tgtype,
TRIGGER_TYPE_ROW,
TRIGGER_TYPE_INSTEAD,
TRIGGER_TYPE_UPDATE))
continue;
if (!TriggerEnabled(estate, relinfo, trigger, LocTriggerData.tg_event,
NULL, oldslot, newslot))
continue;
if (!newtuple)
newtuple = ExecFetchSlotHeapTuple(newslot, true, &should_free);
LocTriggerData.tg_trigslot = oldslot;
LocTriggerData.tg_trigtuple = trigtuple;
LocTriggerData.tg_newslot = newslot;
LocTriggerData.tg_newtuple = oldtuple = newtuple;
LocTriggerData.tg_trigger = trigger;
newtuple = ExecCallTriggerFunc(&LocTriggerData,
i,
relinfo->ri_TrigFunctions,
relinfo->ri_TrigInstrument,
GetPerTupleMemoryContext(estate));
if (newtuple == NULL)
{
return false; /* "do nothing" */
}
else if (newtuple != oldtuple)
{
ExecForceStoreHeapTuple(newtuple, newslot, false);
if (should_free)
heap_freetuple(oldtuple);
/* signal tuple should be re-fetched if used */
newtuple = NULL;
}
}
return true;
}
void
ExecBSTruncateTriggers(EState *estate, ResultRelInfo *relinfo)
{
TriggerDesc *trigdesc;
int i;
TriggerData LocTriggerData;
if (Gp_role == GP_ROLE_EXECUTE)
{
/* Don't fire statement-triggers in executor nodes. */
return;
}
trigdesc = relinfo->ri_TrigDesc;
if (trigdesc == NULL)
return;
if (!trigdesc->trig_truncate_before_statement)
return;
LocTriggerData.type = T_TriggerData;
LocTriggerData.tg_event = TRIGGER_EVENT_TRUNCATE |
TRIGGER_EVENT_BEFORE;
LocTriggerData.tg_relation = relinfo->ri_RelationDesc;
LocTriggerData.tg_trigtuple = NULL;
LocTriggerData.tg_newtuple = NULL;
LocTriggerData.tg_trigslot = NULL;
LocTriggerData.tg_newslot = NULL;
LocTriggerData.tg_oldtable = NULL;
LocTriggerData.tg_newtable = NULL;
for (i = 0; i < trigdesc->numtriggers; i++)
{
Trigger *trigger = &trigdesc->triggers[i];
HeapTuple newtuple;
if (!TRIGGER_TYPE_MATCHES(trigger->tgtype,
TRIGGER_TYPE_STATEMENT,
TRIGGER_TYPE_BEFORE,
TRIGGER_TYPE_TRUNCATE))
continue;
if (!TriggerEnabled(estate, relinfo, trigger, LocTriggerData.tg_event,
NULL, NULL, NULL))
continue;
LocTriggerData.tg_trigger = trigger;
newtuple = ExecCallTriggerFunc(&LocTriggerData,
i,
relinfo->ri_TrigFunctions,
relinfo->ri_TrigInstrument,
GetPerTupleMemoryContext(estate));
if (newtuple)
ereport(ERROR,
(errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
errmsg("BEFORE STATEMENT trigger cannot return a value")));
}
}
void
ExecASTruncateTriggers(EState *estate, ResultRelInfo *relinfo)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
if (trigdesc && trigdesc->trig_truncate_after_statement)
AfterTriggerSaveEvent(estate, relinfo, TRIGGER_EVENT_TRUNCATE,
false, NULL, NULL, NIL, NULL, NULL);
}
static bool
GetTupleForTrigger(EState *estate,
EPQState *epqstate,
ResultRelInfo *relinfo,
ItemPointer tid,
LockTupleMode lockmode,
TupleTableSlot *oldslot,
TupleTableSlot **newSlot)
{
Relation relation = relinfo->ri_RelationDesc;
/* these should be rejected when you try to create such triggers, but let's check */
if (RelationIsAppendOptimized(relation))
elog(ERROR, "UPDATE and DELETE triggers are not supported on append-only tables");
Assert(RelationIsHeap(relation));
if (newSlot != NULL)
{
TM_Result test;
TM_FailureData tmfd;
int lockflags = 0;
*newSlot = NULL;
/* caller must pass an epqstate if EvalPlanQual is possible */
Assert(epqstate != NULL);
/*
* lock tuple for update
*/
if (!IsolationUsesXactSnapshot())
lockflags |= TUPLE_LOCK_FLAG_FIND_LAST_VERSION;
test = table_tuple_lock(relation, tid, estate->es_snapshot, oldslot,
estate->es_output_cid,
lockmode, LockWaitBlock,
lockflags,
&tmfd);
switch (test)
{
case TM_SelfModified:
/*
* The target tuple was already updated or deleted by the
* current command, or by a later command in the current
* transaction. We ignore the tuple in the former case, and
* throw error in the latter case, for the same reasons
* enumerated in ExecUpdate and ExecDelete in
* nodeModifyTable.c.
*/
if (tmfd.cmax != estate->es_output_cid)
ereport(ERROR,
(errcode(ERRCODE_TRIGGERED_DATA_CHANGE_VIOLATION),
errmsg("tuple to be updated was already modified by an operation triggered by the current command"),
errhint("Consider using an AFTER trigger instead of a BEFORE trigger to propagate changes to other rows.")));
/* treat it as deleted; do not process */
return false;
case TM_Ok:
if (tmfd.traversed)
{
TupleTableSlot *epqslot;
epqslot = EvalPlanQual(estate,
epqstate,
relation,
relinfo->ri_RangeTableIndex,
oldslot);
/*
* If PlanQual failed for updated tuple - we must not
* process this tuple!
*/
if (TupIsNull(epqslot))
return false;
*newSlot = epqslot;
}
break;
case TM_Updated:
if (IsolationUsesXactSnapshot())
ereport(ERROR,
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
errmsg("could not serialize access due to concurrent update")));
elog(ERROR, "unexpected table_tuple_lock status: %u", test);
break;
case TM_Deleted:
if (IsolationUsesXactSnapshot())
ereport(ERROR,
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
errmsg("could not serialize access due to concurrent delete")));
/* tuple was deleted */
return false;
case TM_Invisible:
elog(ERROR, "attempted to lock invisible tuple");
break;
default:
elog(ERROR, "unrecognized table_tuple_lock status: %u", test);
return false; /* keep compiler quiet */
}
}
else
{
/*
* We expect the tuple to be present, thus very simple error handling
* suffices.
*/
if (!table_tuple_fetch_row_version(relation, tid, SnapshotAny,
oldslot))
elog(ERROR, "failed to fetch tuple for trigger");
}
return true;
}
/*
* Is trigger enabled to fire?
*/
static bool
TriggerEnabled(EState *estate, ResultRelInfo *relinfo,
Trigger *trigger, TriggerEvent event,
Bitmapset *modifiedCols,
TupleTableSlot *oldslot, TupleTableSlot *newslot)
{
/* Check replication-role-dependent enable state */
if (SessionReplicationRole == SESSION_REPLICATION_ROLE_REPLICA)
{
if (trigger->tgenabled == TRIGGER_FIRES_ON_ORIGIN ||
trigger->tgenabled == TRIGGER_DISABLED)
return false;
}
else /* ORIGIN or LOCAL role */
{
if (trigger->tgenabled == TRIGGER_FIRES_ON_REPLICA ||
trigger->tgenabled == TRIGGER_DISABLED)
return false;
}
/*
* Check for column-specific trigger (only possible for UPDATE, and in
* fact we *must* ignore tgattr for other event types)
*/
if (trigger->tgnattr > 0 && TRIGGER_FIRED_BY_UPDATE(event))
{
int i;
bool modified;
modified = false;
for (i = 0; i < trigger->tgnattr; i++)
{
if (bms_is_member(trigger->tgattr[i] - FirstLowInvalidHeapAttributeNumber,
modifiedCols))
{
modified = true;
break;
}
}
if (!modified)
return false;
}
/* Check for WHEN clause */
if (trigger->tgqual)
{
ExprState **predicate;
ExprContext *econtext;
MemoryContext oldContext;
int i;
Assert(estate != NULL);
/*
* trigger is an element of relinfo->ri_TrigDesc->triggers[]; find the
* matching element of relinfo->ri_TrigWhenExprs[]
*/
i = trigger - relinfo->ri_TrigDesc->triggers;
predicate = &relinfo->ri_TrigWhenExprs[i];
/*
* If first time through for this WHEN expression, build expression
* nodetrees for it. Keep them in the per-query memory context so
* they'll survive throughout the query.
*/
if (*predicate == NULL)
{
Node *tgqual;
oldContext = MemoryContextSwitchTo(estate->es_query_cxt);
tgqual = stringToNode(trigger->tgqual);
/* Change references to OLD and NEW to INNER_VAR and OUTER_VAR */
ChangeVarNodes(tgqual, PRS2_OLD_VARNO, INNER_VAR, 0);
ChangeVarNodes(tgqual, PRS2_NEW_VARNO, OUTER_VAR, 0);
/* ExecPrepareQual wants implicit-AND form */
tgqual = (Node *) make_ands_implicit((Expr *) tgqual);
*predicate = ExecPrepareQual((List *) tgqual, estate);
MemoryContextSwitchTo(oldContext);
}
/*
* We will use the EState's per-tuple context for evaluating WHEN
* expressions (creating it if it's not already there).
*/
econtext = GetPerTupleExprContext(estate);
/*
* Finally evaluate the expression, making the old and/or new tuples
* available as INNER_VAR/OUTER_VAR respectively.
*/
econtext->ecxt_innertuple = oldslot;
econtext->ecxt_outertuple = newslot;
if (!ExecQual(*predicate, econtext))
return false;
}
return true;
}
/* ----------
* After-trigger stuff
*
* The AfterTriggersData struct holds data about pending AFTER trigger events
* during the current transaction tree. (BEFORE triggers are fired
* immediately so we don't need any persistent state about them.) The struct
* and most of its subsidiary data are kept in TopTransactionContext; however
* some data that can be discarded sooner appears in the CurTransactionContext
* of the relevant subtransaction. Also, the individual event records are
* kept in a separate sub-context of TopTransactionContext. This is done
* mainly so that it's easy to tell from a memory context dump how much space
* is being eaten by trigger events.
*
* Because the list of pending events can grow large, we go to some
* considerable effort to minimize per-event memory consumption. The event
* records are grouped into chunks and common data for similar events in the
* same chunk is only stored once.
*
* XXX We need to be able to save the per-event data in a file if it grows too
* large.
* ----------
*/
/* Per-trigger SET CONSTRAINT status */
typedef struct SetConstraintTriggerData
{
Oid sct_tgoid;
bool sct_tgisdeferred;
} SetConstraintTriggerData;
typedef struct SetConstraintTriggerData *SetConstraintTrigger;
/*
* SET CONSTRAINT intra-transaction status.
*
* We make this a single palloc'd object so it can be copied and freed easily.
*
* all_isset and all_isdeferred are used to keep track
* of SET CONSTRAINTS ALL {DEFERRED, IMMEDIATE}.
*
* trigstates[] stores per-trigger tgisdeferred settings.
*/
typedef struct SetConstraintStateData
{
bool all_isset;
bool all_isdeferred;
int numstates; /* number of trigstates[] entries in use */
int numalloc; /* allocated size of trigstates[] */
SetConstraintTriggerData trigstates[FLEXIBLE_ARRAY_MEMBER];
} SetConstraintStateData;
typedef SetConstraintStateData *SetConstraintState;
/*
* Per-trigger-event data
*
* The actual per-event data, AfterTriggerEventData, includes DONE/IN_PROGRESS
* status bits and up to two tuple CTIDs. Each event record also has an
* associated AfterTriggerSharedData that is shared across all instances of
* similar events within a "chunk".
*
* For row-level triggers, we arrange not to waste storage on unneeded ctid
* fields. Updates of regular tables use two; inserts and deletes of regular
* tables use one; foreign tables always use zero and save the tuple(s) to a
* tuplestore. AFTER_TRIGGER_FDW_FETCH directs AfterTriggerExecute() to
* retrieve a fresh tuple or pair of tuples from that tuplestore, while
* AFTER_TRIGGER_FDW_REUSE directs it to use the most-recently-retrieved
* tuple(s). This permits storing tuples once regardless of the number of
* row-level triggers on a foreign table.
*
* Note that we need triggers on foreign tables to be fired in exactly the
* order they were queued, so that the tuples come out of the tuplestore in
* the right order. To ensure that, we forbid deferrable (constraint)
* triggers on foreign tables. This also ensures that such triggers do not
* get deferred into outer trigger query levels, meaning that it's okay to
* destroy the tuplestore at the end of the query level.
*
* Statement-level triggers always bear AFTER_TRIGGER_1CTID, though they
* require no ctid field. We lack the flag bit space to neatly represent that
* distinct case, and it seems unlikely to be worth much trouble.
*
* Note: ats_firing_id is initially zero and is set to something else when
* AFTER_TRIGGER_IN_PROGRESS is set. It indicates which trigger firing
* cycle the trigger will be fired in (or was fired in, if DONE is set).
* Although this is mutable state, we can keep it in AfterTriggerSharedData
* because all instances of the same type of event in a given event list will
* be fired at the same time, if they were queued between the same firing
* cycles. So we need only ensure that ats_firing_id is zero when attaching
* a new event to an existing AfterTriggerSharedData record.
*/
typedef uint32 TriggerFlags;
#define AFTER_TRIGGER_OFFSET 0x0FFFFFFF /* must be low-order bits */
#define AFTER_TRIGGER_DONE 0x10000000
#define AFTER_TRIGGER_IN_PROGRESS 0x20000000
/* bits describing the size and tuple sources of this event */
#define AFTER_TRIGGER_FDW_REUSE 0x00000000
#define AFTER_TRIGGER_FDW_FETCH 0x80000000
#define AFTER_TRIGGER_1CTID 0x40000000
#define AFTER_TRIGGER_2CTID 0xC0000000
#define AFTER_TRIGGER_TUP_BITS 0xC0000000
typedef struct AfterTriggerSharedData *AfterTriggerShared;
typedef struct AfterTriggerSharedData
{
TriggerEvent ats_event; /* event type indicator, see trigger.h */
Oid ats_tgoid; /* the trigger's ID */
Oid ats_relid; /* the relation it's on */
CommandId ats_firing_id; /* ID for firing cycle */
struct AfterTriggersTableData *ats_table; /* transition table access */
} AfterTriggerSharedData;
typedef struct AfterTriggerEventData *AfterTriggerEvent;
typedef struct AfterTriggerEventData
{
TriggerFlags ate_flags; /* status bits and offset to shared data */
ItemPointerData ate_ctid1; /* inserted, deleted, or old updated tuple */
ItemPointerData ate_ctid2; /* new updated tuple */
} AfterTriggerEventData;
/* AfterTriggerEventData, minus ate_ctid2 */
typedef struct AfterTriggerEventDataOneCtid
{
TriggerFlags ate_flags; /* status bits and offset to shared data */
ItemPointerData ate_ctid1; /* inserted, deleted, or old updated tuple */
} AfterTriggerEventDataOneCtid;
/* AfterTriggerEventData, minus ate_ctid1 and ate_ctid2 */
typedef struct AfterTriggerEventDataZeroCtids
{
TriggerFlags ate_flags; /* status bits and offset to shared data */
} AfterTriggerEventDataZeroCtids;
#define SizeofTriggerEvent(evt) \
(((evt)->ate_flags & AFTER_TRIGGER_TUP_BITS) == AFTER_TRIGGER_2CTID ? \
sizeof(AfterTriggerEventData) : \
((evt)->ate_flags & AFTER_TRIGGER_TUP_BITS) == AFTER_TRIGGER_1CTID ? \
sizeof(AfterTriggerEventDataOneCtid) : \
sizeof(AfterTriggerEventDataZeroCtids))
#define GetTriggerSharedData(evt) \
((AfterTriggerShared) ((char *) (evt) + ((evt)->ate_flags & AFTER_TRIGGER_OFFSET)))
/*
* To avoid palloc overhead, we keep trigger events in arrays in successively-
* larger chunks (a slightly more sophisticated version of an expansible
* array). The space between CHUNK_DATA_START and freeptr is occupied by
* AfterTriggerEventData records; the space between endfree and endptr is
* occupied by AfterTriggerSharedData records.
*/
typedef struct AfterTriggerEventChunk
{
struct AfterTriggerEventChunk *next; /* list link */
char *freeptr; /* start of free space in chunk */
char *endfree; /* end of free space in chunk */
char *endptr; /* end of chunk */
/* event data follows here */
} AfterTriggerEventChunk;
#define CHUNK_DATA_START(cptr) ((char *) (cptr) + MAXALIGN(sizeof(AfterTriggerEventChunk)))
/* A list of events */
typedef struct AfterTriggerEventList
{
AfterTriggerEventChunk *head;
AfterTriggerEventChunk *tail;
char *tailfree; /* freeptr of tail chunk */
} AfterTriggerEventList;
/* Macros to help in iterating over a list of events */
#define for_each_chunk(cptr, evtlist) \
for (cptr = (evtlist).head; cptr != NULL; cptr = cptr->next)
#define for_each_event(eptr, cptr) \
for (eptr = (AfterTriggerEvent) CHUNK_DATA_START(cptr); \
(char *) eptr < (cptr)->freeptr; \
eptr = (AfterTriggerEvent) (((char *) eptr) + SizeofTriggerEvent(eptr)))
/* Use this if no special per-chunk processing is needed */
#define for_each_event_chunk(eptr, cptr, evtlist) \
for_each_chunk(cptr, evtlist) for_each_event(eptr, cptr)
/* Macros for iterating from a start point that might not be list start */
#define for_each_chunk_from(cptr) \
for (; cptr != NULL; cptr = cptr->next)
#define for_each_event_from(eptr, cptr) \
for (; \
(char *) eptr < (cptr)->freeptr; \
eptr = (AfterTriggerEvent) (((char *) eptr) + SizeofTriggerEvent(eptr)))
/*
* All per-transaction data for the AFTER TRIGGERS module.
*
* AfterTriggersData has the following fields:
*
* firing_counter is incremented for each call of afterTriggerInvokeEvents.
* We mark firable events with the current firing cycle's ID so that we can
* tell which ones to work on. This ensures sane behavior if a trigger
* function chooses to do SET CONSTRAINTS: the inner SET CONSTRAINTS will
* only fire those events that weren't already scheduled for firing.
*
* state keeps track of the transaction-local effects of SET CONSTRAINTS.
* This is saved and restored across failed subtransactions.
*
* events is the current list of deferred events. This is global across
* all subtransactions of the current transaction. In a subtransaction
* abort, we know that the events added by the subtransaction are at the
* end of the list, so it is relatively easy to discard them. The event
* list chunks themselves are stored in event_cxt.
*
* query_depth is the current depth of nested AfterTriggerBeginQuery calls
* (-1 when the stack is empty).
*
* query_stack[query_depth] is the per-query-level data, including these fields:
*
* events is a list of AFTER trigger events queued by the current query.
* None of these are valid until the matching AfterTriggerEndQuery call
* occurs. At that point we fire immediate-mode triggers, and append any
* deferred events to the main events list.
*
* fdw_tuplestore is a tuplestore containing the foreign-table tuples
* needed by events queued by the current query. (Note: we use just one
* tuplestore even though more than one foreign table might be involved.
* This is okay because tuplestores don't really care what's in the tuples
* they store; but it's possible that someday it'd break.)
*
* tables is a List of AfterTriggersTableData structs for target tables
* of the current query (see below).
*
* maxquerydepth is just the allocated length of query_stack.
*
* trans_stack holds per-subtransaction data, including these fields:
*
* state is NULL or a pointer to a saved copy of the SET CONSTRAINTS
* state data. Each subtransaction level that modifies that state first
* saves a copy, which we use to restore the state if we abort.
*
* events is a copy of the events head/tail pointers,
* which we use to restore those values during subtransaction abort.
*
* query_depth is the subtransaction-start-time value of query_depth,
* which we similarly use to clean up at subtransaction abort.
*
* firing_counter is the subtransaction-start-time value of firing_counter.
* We use this to recognize which deferred triggers were fired (or marked
* for firing) within an aborted subtransaction.
*
* We use GetCurrentTransactionNestLevel() to determine the correct array
* index in trans_stack. maxtransdepth is the number of allocated entries in
* trans_stack. (By not keeping our own stack pointer, we can avoid trouble
* in cases where errors during subxact abort cause multiple invocations
* of AfterTriggerEndSubXact() at the same nesting depth.)
*
* We create an AfterTriggersTableData struct for each target table of the
* current query, and each operation mode (INSERT/UPDATE/DELETE), that has
* either transition tables or statement-level triggers. This is used to
* hold the relevant transition tables, as well as info tracking whether
* we already queued the statement triggers. (We use that info to prevent
* firing the same statement triggers more than once per statement, or really
* once per transition table set.) These structs, along with the transition
* table tuplestores, live in the (sub)transaction's CurTransactionContext.
* That's sufficient lifespan because we don't allow transition tables to be
* used by deferrable triggers, so they only need to survive until
* AfterTriggerEndQuery.
*/
typedef struct AfterTriggersQueryData AfterTriggersQueryData;
typedef struct AfterTriggersTransData AfterTriggersTransData;
typedef struct AfterTriggersTableData AfterTriggersTableData;
typedef struct AfterTriggersData
{
CommandId firing_counter; /* next firing ID to assign */
SetConstraintState state; /* the active S C state */
AfterTriggerEventList events; /* deferred-event list */
MemoryContext event_cxt; /* memory context for events, if any */
/* per-query-level data: */
AfterTriggersQueryData *query_stack; /* array of structs shown below */
int query_depth; /* current index in above array */
int maxquerydepth; /* allocated len of above array */
/* per-subtransaction-level data: */
AfterTriggersTransData *trans_stack; /* array of structs shown below */
int maxtransdepth; /* allocated len of above array */
} AfterTriggersData;
struct AfterTriggersQueryData
{
AfterTriggerEventList events; /* events pending from this query */
Tuplestorestate *fdw_tuplestore; /* foreign tuples for said events */
List *tables; /* list of AfterTriggersTableData, see below */
};
struct AfterTriggersTransData
{
/* these fields are just for resetting at subtrans abort: */
SetConstraintState state; /* saved S C state, or NULL if not yet saved */
AfterTriggerEventList events; /* saved list pointer */
int query_depth; /* saved query_depth */
CommandId firing_counter; /* saved firing_counter */
};
struct AfterTriggersTableData
{
/* relid + cmdType form the lookup key for these structs: */
Oid relid; /* target table's OID */
CmdType cmdType; /* event type, CMD_INSERT/UPDATE/DELETE */
bool closed; /* true when no longer OK to add tuples */
bool before_trig_done; /* did we already queue BS triggers? */
bool after_trig_done; /* did we already queue AS triggers? */
AfterTriggerEventList after_trig_events; /* if so, saved list pointer */
Tuplestorestate *old_tuplestore; /* "old" transition table, if any */
Tuplestorestate *new_tuplestore; /* "new" transition table, if any */
TupleTableSlot *storeslot; /* for converting to tuplestore's format */
};
static AfterTriggersData afterTriggers;
static void AfterTriggerExecute(EState *estate,
AfterTriggerEvent event,
ResultRelInfo *relInfo,
TriggerDesc *trigdesc,
FmgrInfo *finfo,
Instrumentation *instr,
MemoryContext per_tuple_context,
TupleTableSlot *trig_tuple_slot1,
TupleTableSlot *trig_tuple_slot2);
static AfterTriggersTableData *GetAfterTriggersTableData(Oid relid,
CmdType cmdType);
static void AfterTriggerFreeQuery(AfterTriggersQueryData *qs);
static SetConstraintState SetConstraintStateCreate(int numalloc);
static SetConstraintState SetConstraintStateCopy(SetConstraintState state);
static SetConstraintState SetConstraintStateAddItem(SetConstraintState state,
Oid tgoid, bool tgisdeferred);
static void cancel_prior_stmt_triggers(Oid relid, CmdType cmdType, int tgevent);
/*
* Get the FDW tuplestore for the current trigger query level, creating it
* if necessary.
*/
static Tuplestorestate *
GetCurrentFDWTuplestore(void)
{
Tuplestorestate *ret;
ret = afterTriggers.query_stack[afterTriggers.query_depth].fdw_tuplestore;
if (ret == NULL)
{
MemoryContext oldcxt;
ResourceOwner saveResourceOwner;
/*
* Make the tuplestore valid until end of subtransaction. We really
* only need it until AfterTriggerEndQuery().
*/
oldcxt = MemoryContextSwitchTo(CurTransactionContext);
saveResourceOwner = CurrentResourceOwner;
CurrentResourceOwner = CurTransactionResourceOwner;
ret = tuplestore_begin_heap(false, false, work_mem);
CurrentResourceOwner = saveResourceOwner;
MemoryContextSwitchTo(oldcxt);
afterTriggers.query_stack[afterTriggers.query_depth].fdw_tuplestore = ret;
}
return ret;
}
/* ----------
* afterTriggerCheckState()
*
* Returns true if the trigger event is actually in state DEFERRED.
* ----------
*/
static bool
afterTriggerCheckState(AfterTriggerShared evtshared)
{
Oid tgoid = evtshared->ats_tgoid;
SetConstraintState state = afterTriggers.state;
int i;
/*
* For not-deferrable triggers (i.e. normal AFTER ROW triggers and
* constraints declared NOT DEFERRABLE), the state is always false.
*/
if ((evtshared->ats_event & AFTER_TRIGGER_DEFERRABLE) == 0)
return false;
/*
* If constraint state exists, SET CONSTRAINTS might have been executed
* either for this trigger or for all triggers.
*/
if (state != NULL)
{
/* Check for SET CONSTRAINTS for this specific trigger. */
for (i = 0; i < state->numstates; i++)
{
if (state->trigstates[i].sct_tgoid == tgoid)
return state->trigstates[i].sct_tgisdeferred;
}
/* Check for SET CONSTRAINTS ALL. */
if (state->all_isset)
return state->all_isdeferred;
}
/*
* Otherwise return the default state for the trigger.
*/
return ((evtshared->ats_event & AFTER_TRIGGER_INITDEFERRED) != 0);
}
/* ----------
* afterTriggerAddEvent()
*
* Add a new trigger event to the specified queue.
* The passed-in event data is copied.
* ----------
*/
static void
afterTriggerAddEvent(AfterTriggerEventList *events,
AfterTriggerEvent event, AfterTriggerShared evtshared)
{
Size eventsize = SizeofTriggerEvent(event);
Size needed = eventsize + sizeof(AfterTriggerSharedData);
AfterTriggerEventChunk *chunk;
AfterTriggerShared newshared;
AfterTriggerEvent newevent;
/*
* If empty list or not enough room in the tail chunk, make a new chunk.
* We assume here that a new shared record will always be needed.
*/
chunk = events->tail;
if (chunk == NULL ||
chunk->endfree - chunk->freeptr < needed)
{
Size chunksize;
/* Create event context if we didn't already */
if (afterTriggers.event_cxt == NULL)
afterTriggers.event_cxt =
AllocSetContextCreate(TopTransactionContext,
"AfterTriggerEvents",
ALLOCSET_DEFAULT_SIZES);
/*
* Chunk size starts at 1KB and is allowed to increase up to 1MB.
* These numbers are fairly arbitrary, though there is a hard limit at
* AFTER_TRIGGER_OFFSET; else we couldn't link event records to their
* shared records using the available space in ate_flags. Another
* constraint is that if the chunk size gets too huge, the search loop
* below would get slow given a (not too common) usage pattern with
* many distinct event types in a chunk. Therefore, we double the
* preceding chunk size only if there weren't too many shared records
* in the preceding chunk; otherwise we halve it. This gives us some
* ability to adapt to the actual usage pattern of the current query
* while still having large chunk sizes in typical usage. All chunk
* sizes used should be MAXALIGN multiples, to ensure that the shared
* records will be aligned safely.
*/
#define MIN_CHUNK_SIZE 1024
#define MAX_CHUNK_SIZE (1024*1024)
#if MAX_CHUNK_SIZE > (AFTER_TRIGGER_OFFSET+1)
#error MAX_CHUNK_SIZE must not exceed AFTER_TRIGGER_OFFSET
#endif
if (chunk == NULL)
chunksize = MIN_CHUNK_SIZE;
else
{
/* preceding chunk size... */
chunksize = chunk->endptr - (char *) chunk;
/* check number of shared records in preceding chunk */
if ((chunk->endptr - chunk->endfree) <=
(100 * sizeof(AfterTriggerSharedData)))
chunksize *= 2; /* okay, double it */
else
chunksize /= 2; /* too many shared records */
chunksize = Min(chunksize, MAX_CHUNK_SIZE);
}
chunk = MemoryContextAlloc(afterTriggers.event_cxt, chunksize);
chunk->next = NULL;
chunk->freeptr = CHUNK_DATA_START(chunk);
chunk->endptr = chunk->endfree = (char *) chunk + chunksize;
Assert(chunk->endfree - chunk->freeptr >= needed);
if (events->head == NULL)
events->head = chunk;
else
events->tail->next = chunk;
events->tail = chunk;
/* events->tailfree is now out of sync, but we'll fix it below */
}
/*
* Try to locate a matching shared-data record already in the chunk. If
* none, make a new one.
*/
for (newshared = ((AfterTriggerShared) chunk->endptr) - 1;
(char *) newshared >= chunk->endfree;
newshared--)
{
if (newshared->ats_tgoid == evtshared->ats_tgoid &&
newshared->ats_relid == evtshared->ats_relid &&
newshared->ats_event == evtshared->ats_event &&
newshared->ats_table == evtshared->ats_table &&
newshared->ats_firing_id == 0)
break;
}
if ((char *) newshared < chunk->endfree)
{
*newshared = *evtshared;
newshared->ats_firing_id = 0; /* just to be sure */
chunk->endfree = (char *) newshared;
}
/* Insert the data */
newevent = (AfterTriggerEvent) chunk->freeptr;
memcpy(newevent, event, eventsize);
/* ... and link the new event to its shared record */
newevent->ate_flags &= ~AFTER_TRIGGER_OFFSET;
newevent->ate_flags |= (char *) newshared - (char *) newevent;
chunk->freeptr += eventsize;
events->tailfree = chunk->freeptr;
}
/* ----------
* afterTriggerFreeEventList()
*
* Free all the event storage in the given list.
* ----------
*/
static void
afterTriggerFreeEventList(AfterTriggerEventList *events)
{
AfterTriggerEventChunk *chunk;
while ((chunk = events->head) != NULL)
{
events->head = chunk->next;
pfree(chunk);
}
events->tail = NULL;
events->tailfree = NULL;
}
/* ----------
* afterTriggerRestoreEventList()
*
* Restore an event list to its prior length, removing all the events
* added since it had the value old_events.
* ----------
*/
static void
afterTriggerRestoreEventList(AfterTriggerEventList *events,
const AfterTriggerEventList *old_events)
{
AfterTriggerEventChunk *chunk;
AfterTriggerEventChunk *next_chunk;
if (old_events->tail == NULL)
{
/* restoring to a completely empty state, so free everything */
afterTriggerFreeEventList(events);
}
else
{
*events = *old_events;
/* free any chunks after the last one we want to keep */
for (chunk = events->tail->next; chunk != NULL; chunk = next_chunk)
{
next_chunk = chunk->next;
pfree(chunk);
}
/* and clean up the tail chunk to be the right length */
events->tail->next = NULL;
events->tail->freeptr = events->tailfree;
/*
* We don't make any effort to remove now-unused shared data records.
* They might still be useful, anyway.
*/
}
}
/* ----------
* afterTriggerDeleteHeadEventChunk()
*
* Remove the first chunk of events from the query level's event list.
* Keep any event list pointers elsewhere in the query level's data
* structures in sync.
* ----------
*/
static void
afterTriggerDeleteHeadEventChunk(AfterTriggersQueryData *qs)
{
AfterTriggerEventChunk *target = qs->events.head;
ListCell *lc;
Assert(target && target->next);
/*
* First, update any pointers in the per-table data, so that they won't be
* dangling. Resetting obsoleted pointers to NULL will make
* cancel_prior_stmt_triggers start from the list head, which is fine.
*/
foreach(lc, qs->tables)
{
AfterTriggersTableData *table = (AfterTriggersTableData *) lfirst(lc);
if (table->after_trig_done &&
table->after_trig_events.tail == target)
{
table->after_trig_events.head = NULL;
table->after_trig_events.tail = NULL;
table->after_trig_events.tailfree = NULL;
}
}
/* Now we can flush the head chunk */
qs->events.head = target->next;
pfree(target);
}
/* ----------
* AfterTriggerExecute()
*
* Fetch the required tuples back from the heap and fire one
* single trigger function.
*
* Frequently, this will be fired many times in a row for triggers of
* a single relation. Therefore, we cache the open relation and provide
* fmgr lookup cache space at the caller level. (For triggers fired at
* the end of a query, we can even piggyback on the executor's state.)
*
* event: event currently being fired.
* rel: open relation for event.
* trigdesc: working copy of rel's trigger info.
* finfo: array of fmgr lookup cache entries (one per trigger in trigdesc).
* instr: array of EXPLAIN ANALYZE instrumentation nodes (one per trigger),
* or NULL if no instrumentation is wanted.
* per_tuple_context: memory context to call trigger function in.
* trig_tuple_slot1: scratch slot for tg_trigtuple (foreign tables only)
* trig_tuple_slot2: scratch slot for tg_newtuple (foreign tables only)
* ----------
*/
static void
AfterTriggerExecute(EState *estate,
AfterTriggerEvent event,
ResultRelInfo *relInfo,
TriggerDesc *trigdesc,
FmgrInfo *finfo, Instrumentation *instr,
MemoryContext per_tuple_context,
TupleTableSlot *trig_tuple_slot1,
TupleTableSlot *trig_tuple_slot2)
{
Relation rel = relInfo->ri_RelationDesc;
AfterTriggerShared evtshared = GetTriggerSharedData(event);
Oid tgoid = evtshared->ats_tgoid;
TriggerData LocTriggerData;
HeapTuple rettuple;
int tgindx;
bool should_free_trig = false;
bool should_free_new = false;
/*
* Locate trigger in trigdesc.
*/
LocTriggerData.tg_trigger = NULL;
LocTriggerData.tg_trigslot = NULL;
LocTriggerData.tg_newslot = NULL;
for (tgindx = 0; tgindx < trigdesc->numtriggers; tgindx++)
{
if (trigdesc->triggers[tgindx].tgoid == tgoid)
{
LocTriggerData.tg_trigger = &(trigdesc->triggers[tgindx]);
break;
}
}
if (LocTriggerData.tg_trigger == NULL)
elog(ERROR, "could not find trigger %u", tgoid);
/*
* If doing EXPLAIN ANALYZE, start charging time to this trigger. We want
* to include time spent re-fetching tuples in the trigger cost.
*/
if (instr)
InstrStartNode(instr + tgindx);
/*
* Fetch the required tuple(s).
*/
switch (event->ate_flags & AFTER_TRIGGER_TUP_BITS)
{
case AFTER_TRIGGER_FDW_FETCH:
{
Tuplestorestate *fdw_tuplestore = GetCurrentFDWTuplestore();
if (!tuplestore_gettupleslot(fdw_tuplestore, true, false,
trig_tuple_slot1))
elog(ERROR, "failed to fetch tuple1 for AFTER trigger");
if ((evtshared->ats_event & TRIGGER_EVENT_OPMASK) ==
TRIGGER_EVENT_UPDATE &&
!tuplestore_gettupleslot(fdw_tuplestore, true, false,
trig_tuple_slot2))
elog(ERROR, "failed to fetch tuple2 for AFTER trigger");
}
/* fall through */
case AFTER_TRIGGER_FDW_REUSE:
/*
* Store tuple in the slot so that tg_trigtuple does not reference
* tuplestore memory. (It is formally possible for the trigger
* function to queue trigger events that add to the same
* tuplestore, which can push other tuples out of memory.) The
* distinction is academic, because we start with a minimal tuple
* that is stored as a heap tuple, constructed in different memory
* context, in the slot anyway.
*/
LocTriggerData.tg_trigslot = trig_tuple_slot1;
LocTriggerData.tg_trigtuple =
ExecFetchSlotHeapTuple(trig_tuple_slot1, true, &should_free_trig);
LocTriggerData.tg_newslot = trig_tuple_slot2;
LocTriggerData.tg_newtuple =
((evtshared->ats_event & TRIGGER_EVENT_OPMASK) ==
TRIGGER_EVENT_UPDATE) ?
ExecFetchSlotHeapTuple(trig_tuple_slot2, true, &should_free_new) : NULL;
break;
default:
if (ItemPointerIsValid(&(event->ate_ctid1)))
{
LocTriggerData.tg_trigslot = ExecGetTriggerOldSlot(estate, relInfo);
if (!table_tuple_fetch_row_version(rel, &(event->ate_ctid1),
SnapshotAny,
LocTriggerData.tg_trigslot))
elog(ERROR, "failed to fetch tuple1 for AFTER trigger");
LocTriggerData.tg_trigtuple =
ExecFetchSlotHeapTuple(LocTriggerData.tg_trigslot, false, &should_free_trig);
}
else
{
LocTriggerData.tg_trigtuple = NULL;
}
/* don't touch ctid2 if not there */
if ((event->ate_flags & AFTER_TRIGGER_TUP_BITS) ==
AFTER_TRIGGER_2CTID &&
ItemPointerIsValid(&(event->ate_ctid2)))
{
LocTriggerData.tg_newslot = ExecGetTriggerNewSlot(estate, relInfo);
if (!table_tuple_fetch_row_version(rel, &(event->ate_ctid2),
SnapshotAny,
LocTriggerData.tg_newslot))
elog(ERROR, "failed to fetch tuple2 for AFTER trigger");
LocTriggerData.tg_newtuple =
ExecFetchSlotHeapTuple(LocTriggerData.tg_newslot, false, &should_free_new);
}
else
{
LocTriggerData.tg_newtuple = NULL;
}
}
/*
* Set up the tuplestore information to let the trigger have access to
* transition tables. When we first make a transition table available to
* a trigger, mark it "closed" so that it cannot change anymore. If any
* additional events of the same type get queued in the current trigger
* query level, they'll go into new transition tables.
*/
LocTriggerData.tg_oldtable = LocTriggerData.tg_newtable = NULL;
if (evtshared->ats_table)
{
if (LocTriggerData.tg_trigger->tgoldtable)
{
LocTriggerData.tg_oldtable = evtshared->ats_table->old_tuplestore;
evtshared->ats_table->closed = true;
}
if (LocTriggerData.tg_trigger->tgnewtable)
{
LocTriggerData.tg_newtable = evtshared->ats_table->new_tuplestore;
evtshared->ats_table->closed = true;
}
}
/*
* Setup the remaining trigger information
*/
LocTriggerData.type = T_TriggerData;
LocTriggerData.tg_event =
evtshared->ats_event & (TRIGGER_EVENT_OPMASK | TRIGGER_EVENT_ROW);
LocTriggerData.tg_relation = rel;
MemoryContextReset(per_tuple_context);
/*
* Call the trigger and throw away any possibly returned updated tuple.
* (Don't let ExecCallTriggerFunc measure EXPLAIN time.)
*/
rettuple = ExecCallTriggerFunc(&LocTriggerData,
tgindx,
finfo,
NULL,
per_tuple_context);
if (rettuple != NULL &&
rettuple != LocTriggerData.tg_trigtuple &&
rettuple != LocTriggerData.tg_newtuple)
heap_freetuple(rettuple);
/*
* Release resources
*/
if (should_free_trig)
heap_freetuple(LocTriggerData.tg_trigtuple);
if (should_free_new)
heap_freetuple(LocTriggerData.tg_newtuple);
if (LocTriggerData.tg_trigslot)
ExecClearTuple(LocTriggerData.tg_trigslot);
if (LocTriggerData.tg_newslot)
ExecClearTuple(LocTriggerData.tg_newslot);
/*
* If doing EXPLAIN ANALYZE, stop charging time to this trigger, and count
* one "tuple returned" (really the number of firings).
*/
if (instr)
InstrStopNode(instr + tgindx, 1);
}
/*
* afterTriggerMarkEvents()
*
* Scan the given event list for not yet invoked events. Mark the ones
* that can be invoked now with the current firing ID.
*
* If move_list isn't NULL, events that are not to be invoked now are
* transferred to move_list.
*
* When immediate_only is true, do not invoke currently-deferred triggers.
* (This will be false only at main transaction exit.)
*
* Returns true if any invokable events were found.
*/
static bool
afterTriggerMarkEvents(AfterTriggerEventList *events,
AfterTriggerEventList *move_list,
bool immediate_only)
{
bool found = false;
bool deferred_found = false;
AfterTriggerEvent event;
AfterTriggerEventChunk *chunk;
for_each_event_chunk(event, chunk, *events)
{
AfterTriggerShared evtshared = GetTriggerSharedData(event);
bool defer_it = false;
if (!(event->ate_flags &
(AFTER_TRIGGER_DONE | AFTER_TRIGGER_IN_PROGRESS)))
{
/*
* This trigger hasn't been called or scheduled yet. Check if we
* should call it now.
*/
if (immediate_only && afterTriggerCheckState(evtshared))
{
defer_it = true;
}
else
{
/*
* Mark it as to be fired in this firing cycle.
*/
evtshared->ats_firing_id = afterTriggers.firing_counter;
event->ate_flags |= AFTER_TRIGGER_IN_PROGRESS;
found = true;
}
}
/*
* If it's deferred, move it to move_list, if requested.
*/
if (defer_it && move_list != NULL)
{
deferred_found = true;
/* add it to move_list */
afterTriggerAddEvent(move_list, event, evtshared);
/* mark original copy "done" so we don't do it again */
event->ate_flags |= AFTER_TRIGGER_DONE;
}
}
/*
* We could allow deferred triggers if, before the end of the
* security-restricted operation, we were to verify that a SET CONSTRAINTS
* ... IMMEDIATE has fired all such triggers. For now, don't bother.
*/
if (deferred_found && InSecurityRestrictedOperation())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("cannot fire deferred trigger within security-restricted operation")));
return found;
}
/*
* afterTriggerInvokeEvents()
*
* Scan the given event list for events that are marked as to be fired
* in the current firing cycle, and fire them. query_depth is the index in
* afterTriggers->query_stack, or -1 to examine afterTriggers->events.
* (We have to be careful here because query_stack could move under us.)
*
* If estate isn't NULL, we use its result relation info to avoid repeated
* openings and closing of trigger target relations. If it is NULL, we
* make one locally to cache the info in case there are multiple trigger
* events per rel.
*
* When delete_ok is true, it's safe to delete fully-processed events.
* (We are not very tense about that: we simply reset a chunk to be empty
* if all its events got fired. The objective here is just to avoid useless
* rescanning of events when a trigger queues new events during transaction
* end, so it's not necessary to worry much about the case where only
* some events are fired.)
*
* Returns true if no unfired events remain in the list (this allows us
* to avoid repeating afterTriggerMarkEvents).
*/
static bool
afterTriggerInvokeEvents(AfterTriggerEventList *events,
CommandId firing_id,
EState *estate,
bool delete_ok)
{
bool all_fired = true;
AfterTriggerEventChunk *chunk;
MemoryContext per_tuple_context;
bool local_estate = false;
ResultRelInfo *rInfo = NULL;
Relation rel = NULL;
TriggerDesc *trigdesc = NULL;
FmgrInfo *finfo = NULL;
Instrumentation *instr = NULL;
TupleTableSlot *slot1 = NULL,
*slot2 = NULL;
/* Make a local EState if need be */
if (estate == NULL)
{
estate = CreateExecutorState();
local_estate = true;
}
/* Make a per-tuple memory context for trigger function calls */
per_tuple_context =
AllocSetContextCreate(CurrentMemoryContext,
"AfterTriggerTupleContext",
ALLOCSET_DEFAULT_SIZES);
for_each_chunk(chunk, *events)
{
AfterTriggerEvent event;
bool all_fired_in_chunk = true;
for_each_event(event, chunk)
{
AfterTriggerShared evtshared = GetTriggerSharedData(event);
/*
* Is it one for me to fire?
*/
if ((event->ate_flags & AFTER_TRIGGER_IN_PROGRESS) &&
evtshared->ats_firing_id == firing_id)
{
/*
* So let's fire it... but first, find the correct relation if
* this is not the same relation as before.
*/
if (rel == NULL || RelationGetRelid(rel) != evtshared->ats_relid)
{
rInfo = ExecGetTriggerResultRel(estate, evtshared->ats_relid);
rel = rInfo->ri_RelationDesc;
trigdesc = rInfo->ri_TrigDesc;
finfo = rInfo->ri_TrigFunctions;
instr = rInfo->ri_TrigInstrument;
if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
{
if (slot1 != NULL)
{
ExecDropSingleTupleTableSlot(slot1);
ExecDropSingleTupleTableSlot(slot2);
}
slot1 = MakeSingleTupleTableSlot(rel->rd_att,
&TTSOpsMinimalTuple);
slot2 = MakeSingleTupleTableSlot(rel->rd_att,
&TTSOpsMinimalTuple);
}
if (trigdesc == NULL) /* should not happen */
elog(ERROR, "relation %u has no triggers",
evtshared->ats_relid);
}
/*
* Fire it. Note that the AFTER_TRIGGER_IN_PROGRESS flag is
* still set, so recursive examinations of the event list
* won't try to re-fire it.
*/
AfterTriggerExecute(estate, event, rInfo, trigdesc, finfo, instr,
per_tuple_context, slot1, slot2);
/*
* Mark the event as done.
*/
event->ate_flags &= ~AFTER_TRIGGER_IN_PROGRESS;
event->ate_flags |= AFTER_TRIGGER_DONE;
}
else if (!(event->ate_flags & AFTER_TRIGGER_DONE))
{
/* something remains to be done */
all_fired = all_fired_in_chunk = false;
}
}
/* Clear the chunk if delete_ok and nothing left of interest */
if (delete_ok && all_fired_in_chunk)
{
chunk->freeptr = CHUNK_DATA_START(chunk);
chunk->endfree = chunk->endptr;
/*
* If it's last chunk, must sync event list's tailfree too. Note
* that delete_ok must NOT be passed as true if there could be
* additional AfterTriggerEventList values pointing at this event
* list, since we'd fail to fix their copies of tailfree.
*/
if (chunk == events->tail)
events->tailfree = chunk->freeptr;
}
}
if (slot1 != NULL)
{
ExecDropSingleTupleTableSlot(slot1);
ExecDropSingleTupleTableSlot(slot2);
}
/* Release working resources */
MemoryContextDelete(per_tuple_context);
if (local_estate)
{
ExecCleanUpTriggerState(estate);
ExecResetTupleTable(estate->es_tupleTable, false);
FreeExecutorState(estate);
}
return all_fired;
}
/*
* GetAfterTriggersTableData
*
* Find or create an AfterTriggersTableData struct for the specified
* trigger event (relation + operation type). Ignore existing structs
* marked "closed"; we don't want to put any additional tuples into them,
* nor change their stmt-triggers-fired state.
*
* Note: the AfterTriggersTableData list is allocated in the current
* (sub)transaction's CurTransactionContext. This is OK because
* we don't need it to live past AfterTriggerEndQuery.
*/
static AfterTriggersTableData *
GetAfterTriggersTableData(Oid relid, CmdType cmdType)
{
AfterTriggersTableData *table;
AfterTriggersQueryData *qs;
MemoryContext oldcxt;
ListCell *lc;
/* Caller should have ensured query_depth is OK. */
Assert(afterTriggers.query_depth >= 0 &&
afterTriggers.query_depth < afterTriggers.maxquerydepth);
qs = &afterTriggers.query_stack[afterTriggers.query_depth];
foreach(lc, qs->tables)
{
table = (AfterTriggersTableData *) lfirst(lc);
if (table->relid == relid && table->cmdType == cmdType &&
!table->closed)
return table;
}
oldcxt = MemoryContextSwitchTo(CurTransactionContext);
table = (AfterTriggersTableData *) palloc0(sizeof(AfterTriggersTableData));
table->relid = relid;
table->cmdType = cmdType;
qs->tables = lappend(qs->tables, table);
MemoryContextSwitchTo(oldcxt);
return table;
}
/*
* MakeTransitionCaptureState
*
* Make a TransitionCaptureState object for the given TriggerDesc, target
* relation, and operation type. The TCS object holds all the state needed
* to decide whether to capture tuples in transition tables.
*
* If there are no triggers in 'trigdesc' that request relevant transition
* tables, then return NULL.
*
* The resulting object can be passed to the ExecAR* functions. The caller
* should set tcs_map or tcs_original_insert_tuple as appropriate when dealing
* with child tables.
*
* Note that we copy the flags from a parent table into this struct (rather
* than subsequently using the relation's TriggerDesc directly) so that we can
* use it to control collection of transition tuples from child tables.
*
* Per SQL spec, all operations of the same kind (INSERT/UPDATE/DELETE)
* on the same table during one query should share one transition table.
* Therefore, the Tuplestores are owned by an AfterTriggersTableData struct
* looked up using the table OID + CmdType, and are merely referenced by
* the TransitionCaptureState objects we hand out to callers.
*/
TransitionCaptureState *
MakeTransitionCaptureState(TriggerDesc *trigdesc, Oid relid, CmdType cmdType)
{
TransitionCaptureState *state;
bool need_old,
need_new;
AfterTriggersTableData *table;
MemoryContext oldcxt;
ResourceOwner saveResourceOwner;
if (trigdesc == NULL)
return NULL;
/* Detect which table(s) we need. */
switch (cmdType)
{
case CMD_INSERT:
need_old = false;
need_new = trigdesc->trig_insert_new_table;
break;
case CMD_UPDATE:
need_old = trigdesc->trig_update_old_table;
need_new = trigdesc->trig_update_new_table;
break;
case CMD_DELETE:
need_old = trigdesc->trig_delete_old_table;
need_new = false;
break;
default:
elog(ERROR, "unexpected CmdType: %d", (int) cmdType);
need_old = need_new = false; /* keep compiler quiet */
break;
}
if (!need_old && !need_new)
return NULL;
/* Check state, like AfterTriggerSaveEvent. */
if (afterTriggers.query_depth < 0)
elog(ERROR, "MakeTransitionCaptureState() called outside of query");
/* Be sure we have enough space to record events at this query depth. */
if (afterTriggers.query_depth >= afterTriggers.maxquerydepth)
AfterTriggerEnlargeQueryState();
/*
* Find or create an AfterTriggersTableData struct to hold the
* tuplestore(s). If there's a matching struct but it's marked closed,
* ignore it; we need a newer one.
*
* Note: the AfterTriggersTableData list, as well as the tuplestores, are
* allocated in the current (sub)transaction's CurTransactionContext, and
* the tuplestores are managed by the (sub)transaction's resource owner.
* This is sufficient lifespan because we do not allow triggers using
* transition tables to be deferrable; they will be fired during
* AfterTriggerEndQuery, after which it's okay to delete the data.
*/
table = GetAfterTriggersTableData(relid, cmdType);
/* Now create required tuplestore(s), if we don't have them already. */
oldcxt = MemoryContextSwitchTo(CurTransactionContext);
saveResourceOwner = CurrentResourceOwner;
CurrentResourceOwner = CurTransactionResourceOwner;
if (need_old && table->old_tuplestore == NULL)
table->old_tuplestore = tuplestore_begin_heap(false, false, work_mem);
if (need_new && table->new_tuplestore == NULL)
table->new_tuplestore = tuplestore_begin_heap(false, false, work_mem);
CurrentResourceOwner = saveResourceOwner;
MemoryContextSwitchTo(oldcxt);
/* Now build the TransitionCaptureState struct, in caller's context */
state = (TransitionCaptureState *) palloc0(sizeof(TransitionCaptureState));
state->tcs_delete_old_table = trigdesc->trig_delete_old_table;
state->tcs_update_old_table = trigdesc->trig_update_old_table;
state->tcs_update_new_table = trigdesc->trig_update_new_table;
state->tcs_insert_new_table = trigdesc->trig_insert_new_table;
state->tcs_private = table;
return state;
}
/* ----------
* AfterTriggerBeginXact()
*
* Called at transaction start (either BEGIN or implicit for single
* statement outside of transaction block).
* ----------
*/
void
AfterTriggerBeginXact(void)
{
/*
* Initialize after-trigger state structure to empty
*/
afterTriggers.firing_counter = (CommandId) 1; /* mustn't be 0 */
afterTriggers.query_depth = -1;
/*
* Verify that there is no leftover state remaining. If these assertions
* trip, it means that AfterTriggerEndXact wasn't called or didn't clean
* up properly.
*/
Assert(afterTriggers.state == NULL);
Assert(afterTriggers.query_stack == NULL);
Assert(afterTriggers.maxquerydepth == 0);
Assert(afterTriggers.event_cxt == NULL);
Assert(afterTriggers.events.head == NULL);
Assert(afterTriggers.trans_stack == NULL);
Assert(afterTriggers.maxtransdepth == 0);
}
/* ----------
* AfterTriggerBeginQuery()
*
* Called just before we start processing a single query within a
* transaction (or subtransaction). Most of the real work gets deferred
* until somebody actually tries to queue a trigger event.
* ----------
*/
void
AfterTriggerBeginQuery(void)
{
/* Increase the query stack depth */
afterTriggers.query_depth++;
}
/* ----------
* AfterTriggerEndQuery()
*
* Called after one query has been completely processed. At this time
* we invoke all AFTER IMMEDIATE trigger events queued by the query, and
* transfer deferred trigger events to the global deferred-trigger list.
*
* Note that this must be called BEFORE closing down the executor
* with ExecutorEnd, because we make use of the EState's info about
* target relations. Normally it is called from ExecutorFinish.
* ----------
*/
void
AfterTriggerEndQuery(EState *estate)
{
AfterTriggersQueryData *qs;
/* Must be inside a query, too */
Assert(afterTriggers.query_depth >= 0);
/*
* If we never even got as far as initializing the event stack, there
* certainly won't be any events, so exit quickly.
*/
if (afterTriggers.query_depth >= afterTriggers.maxquerydepth)
{
afterTriggers.query_depth--;
return;
}
/*
* Process all immediate-mode triggers queued by the query, and move the
* deferred ones to the main list of deferred events.
*
* Notice that we decide which ones will be fired, and put the deferred
* ones on the main list, before anything is actually fired. This ensures
* reasonably sane behavior if a trigger function does SET CONSTRAINTS ...
* IMMEDIATE: all events we have decided to defer will be available for it
* to fire.
*
* We loop in case a trigger queues more events at the same query level.
* Ordinary trigger functions, including all PL/pgSQL trigger functions,
* will instead fire any triggers in a dedicated query level. Foreign key
* enforcement triggers do add to the current query level, thanks to their
* passing fire_triggers = false to SPI_execute_snapshot(). Other
* C-language triggers might do likewise.
*
* If we find no firable events, we don't have to increment
* firing_counter.
*/
qs = &afterTriggers.query_stack[afterTriggers.query_depth];
for (;;)
{
if (afterTriggerMarkEvents(&qs->events, &afterTriggers.events, true))
{
CommandId firing_id = afterTriggers.firing_counter++;
AfterTriggerEventChunk *oldtail = qs->events.tail;
if (afterTriggerInvokeEvents(&qs->events, firing_id, estate, false))
break; /* all fired */
/*
* Firing a trigger could result in query_stack being repalloc'd,
* so we must recalculate qs after each afterTriggerInvokeEvents
* call. Furthermore, it's unsafe to pass delete_ok = true here,
* because that could cause afterTriggerInvokeEvents to try to
* access qs->events after the stack has been repalloc'd.
*/
qs = &afterTriggers.query_stack[afterTriggers.query_depth];
/*
* We'll need to scan the events list again. To reduce the cost
* of doing so, get rid of completely-fired chunks. We know that
* all events were marked IN_PROGRESS or DONE at the conclusion of
* afterTriggerMarkEvents, so any still-interesting events must
* have been added after that, and so must be in the chunk that
* was then the tail chunk, or in later chunks. So, zap all
* chunks before oldtail. This is approximately the same set of
* events we would have gotten rid of by passing delete_ok = true.
*/
Assert(oldtail != NULL);
while (qs->events.head != oldtail)
afterTriggerDeleteHeadEventChunk(qs);
}
else
break;
}
/* Release query-level-local storage, including tuplestores if any */
AfterTriggerFreeQuery(&afterTriggers.query_stack[afterTriggers.query_depth]);
afterTriggers.query_depth--;
}
/*
* AfterTriggerFreeQuery
* Release subsidiary storage for a trigger query level.
* This includes closing down tuplestores.
* Note: it's important for this to be safe if interrupted by an error
* and then called again for the same query level.
*/
static void
AfterTriggerFreeQuery(AfterTriggersQueryData *qs)
{
Tuplestorestate *ts;
List *tables;
ListCell *lc;
/* Drop the trigger events */
afterTriggerFreeEventList(&qs->events);
/* Drop FDW tuplestore if any */
ts = qs->fdw_tuplestore;
qs->fdw_tuplestore = NULL;
if (ts)
tuplestore_end(ts);
/* Release per-table subsidiary storage */
tables = qs->tables;
foreach(lc, tables)
{
AfterTriggersTableData *table = (AfterTriggersTableData *) lfirst(lc);
ts = table->old_tuplestore;
table->old_tuplestore = NULL;
if (ts)
tuplestore_end(ts);
ts = table->new_tuplestore;
table->new_tuplestore = NULL;
if (ts)
tuplestore_end(ts);
}
/*
* Now free the AfterTriggersTableData structs and list cells. Reset list
* pointer first; if list_free_deep somehow gets an error, better to leak
* that storage than have an infinite loop.
*/
qs->tables = NIL;
list_free_deep(tables);
}
/* ----------
* AfterTriggerFireDeferred()
*
* Called just before the current transaction is committed. At this
* time we invoke all pending DEFERRED triggers.
*
* It is possible for other modules to queue additional deferred triggers
* during pre-commit processing; therefore xact.c may have to call this
* multiple times.
* ----------
*/
void
AfterTriggerFireDeferred(void)
{
AfterTriggerEventList *events;
bool snap_pushed = false;
/* Must not be inside a query */
Assert(afterTriggers.query_depth == -1);
/*
* If there are any triggers to fire, make sure we have set a snapshot for
* them to use. (Since PortalRunUtility doesn't set a snap for COMMIT, we
* can't assume ActiveSnapshot is valid on entry.)
*/
events = &afterTriggers.events;
if (events->head != NULL)
{
PushActiveSnapshot(GetTransactionSnapshot());
snap_pushed = true;
}
/*
* Run all the remaining triggers. Loop until they are all gone, in case
* some trigger queues more for us to do.
*/
while (afterTriggerMarkEvents(events, NULL, false))
{
CommandId firing_id = afterTriggers.firing_counter++;
if (afterTriggerInvokeEvents(events, firing_id, NULL, true))
break; /* all fired */
}
/*
* We don't bother freeing the event list, since it will go away anyway
* (and more efficiently than via pfree) in AfterTriggerEndXact.
*/
if (snap_pushed)
PopActiveSnapshot();
}
/* ----------
* AfterTriggerEndXact()
*
* The current transaction is finishing.
*
* Any unfired triggers are canceled so we simply throw
* away anything we know.
*
* Note: it is possible for this to be called repeatedly in case of
* error during transaction abort; therefore, do not complain if
* already closed down.
* ----------
*/
void
AfterTriggerEndXact(bool isCommit)
{
/*
* Forget the pending-events list.
*
* Since all the info is in TopTransactionContext or children thereof, we
* don't really need to do anything to reclaim memory. However, the
* pending-events list could be large, and so it's useful to discard it as
* soon as possible --- especially if we are aborting because we ran out
* of memory for the list!
*/
if (afterTriggers.event_cxt)
{
MemoryContextDelete(afterTriggers.event_cxt);
afterTriggers.event_cxt = NULL;
afterTriggers.events.head = NULL;
afterTriggers.events.tail = NULL;
afterTriggers.events.tailfree = NULL;
}
/*
* Forget any subtransaction state as well. Since this can't be very
* large, we let the eventual reset of TopTransactionContext free the
* memory instead of doing it here.
*/
afterTriggers.trans_stack = NULL;
afterTriggers.maxtransdepth = 0;
/*
* Forget the query stack and constraint-related state information. As
* with the subtransaction state information, we don't bother freeing the
* memory here.
*/
afterTriggers.query_stack = NULL;
afterTriggers.maxquerydepth = 0;
afterTriggers.state = NULL;
/* No more afterTriggers manipulation until next transaction starts. */
afterTriggers.query_depth = -1;
}
/*
* AfterTriggerBeginSubXact()
*
* Start a subtransaction.
*/
void
AfterTriggerBeginSubXact(void)
{
int my_level = GetCurrentTransactionNestLevel();
/*
* Allocate more space in the trans_stack if needed. (Note: because the
* minimum nest level of a subtransaction is 2, we waste the first couple
* entries of the array; not worth the notational effort to avoid it.)
*/
while (my_level >= afterTriggers.maxtransdepth)
{
if (afterTriggers.maxtransdepth == 0)
{
/* Arbitrarily initialize for max of 8 subtransaction levels */
afterTriggers.trans_stack = (AfterTriggersTransData *)
MemoryContextAlloc(TopTransactionContext,
8 * sizeof(AfterTriggersTransData));
afterTriggers.maxtransdepth = 8;
}
else
{
/* repalloc will keep the stack in the same context */
int new_alloc = afterTriggers.maxtransdepth * 2;
afterTriggers.trans_stack = (AfterTriggersTransData *)
repalloc(afterTriggers.trans_stack,
new_alloc * sizeof(AfterTriggersTransData));
afterTriggers.maxtransdepth = new_alloc;
}
}
/*
* Push the current information into the stack. The SET CONSTRAINTS state
* is not saved until/unless changed. Likewise, we don't make a
* per-subtransaction event context until needed.
*/
afterTriggers.trans_stack[my_level].state = NULL;
afterTriggers.trans_stack[my_level].events = afterTriggers.events;
afterTriggers.trans_stack[my_level].query_depth = afterTriggers.query_depth;
afterTriggers.trans_stack[my_level].firing_counter = afterTriggers.firing_counter;
}
/*
* AfterTriggerEndSubXact()
*
* The current subtransaction is ending.
*/
void
AfterTriggerEndSubXact(bool isCommit)
{
int my_level = GetCurrentTransactionNestLevel();
SetConstraintState state;
AfterTriggerEvent event;
AfterTriggerEventChunk *chunk;
CommandId subxact_firing_id;
/*
* Pop the prior state if needed.
*/
if (isCommit)
{
Assert(my_level < afterTriggers.maxtransdepth);
/* If we saved a prior state, we don't need it anymore */
state = afterTriggers.trans_stack[my_level].state;
if (state != NULL)
pfree(state);
/* this avoids double pfree if error later: */
afterTriggers.trans_stack[my_level].state = NULL;
Assert(afterTriggers.query_depth ==
afterTriggers.trans_stack[my_level].query_depth);
}
else
{
/*
* Aborting. It is possible subxact start failed before calling
* AfterTriggerBeginSubXact, in which case we mustn't risk touching
* trans_stack levels that aren't there.
*/
if (my_level >= afterTriggers.maxtransdepth)
return;
/*
* Release query-level storage for queries being aborted, and restore
* query_depth to its pre-subxact value. This assumes that a
* subtransaction will not add events to query levels started in a
* earlier transaction state.
*/
while (afterTriggers.query_depth > afterTriggers.trans_stack[my_level].query_depth)
{
if (afterTriggers.query_depth < afterTriggers.maxquerydepth)
AfterTriggerFreeQuery(&afterTriggers.query_stack[afterTriggers.query_depth]);
afterTriggers.query_depth--;
}
Assert(afterTriggers.query_depth ==
afterTriggers.trans_stack[my_level].query_depth);
/*
* Restore the global deferred-event list to its former length,
* discarding any events queued by the subxact.
*/
afterTriggerRestoreEventList(&afterTriggers.events,
&afterTriggers.trans_stack[my_level].events);
/*
* Restore the trigger state. If the saved state is NULL, then this
* subxact didn't save it, so it doesn't need restoring.
*/
state = afterTriggers.trans_stack[my_level].state;
if (state != NULL)
{
pfree(afterTriggers.state);
afterTriggers.state = state;
}
/* this avoids double pfree if error later: */
afterTriggers.trans_stack[my_level].state = NULL;
/*
* Scan for any remaining deferred events that were marked DONE or IN
* PROGRESS by this subxact or a child, and un-mark them. We can
* recognize such events because they have a firing ID greater than or
* equal to the firing_counter value we saved at subtransaction start.
* (This essentially assumes that the current subxact includes all
* subxacts started after it.)
*/
subxact_firing_id = afterTriggers.trans_stack[my_level].firing_counter;
for_each_event_chunk(event, chunk, afterTriggers.events)
{
AfterTriggerShared evtshared = GetTriggerSharedData(event);
if (event->ate_flags &
(AFTER_TRIGGER_DONE | AFTER_TRIGGER_IN_PROGRESS))
{
if (evtshared->ats_firing_id >= subxact_firing_id)
event->ate_flags &=
~(AFTER_TRIGGER_DONE | AFTER_TRIGGER_IN_PROGRESS);
}
}
}
}
/* ----------
* AfterTriggerEnlargeQueryState()
*
* Prepare the necessary state so that we can record AFTER trigger events
* queued by a query. It is allowed to have nested queries within a
* (sub)transaction, so we need to have separate state for each query
* nesting level.
* ----------
*/
static void
AfterTriggerEnlargeQueryState(void)
{
int init_depth = afterTriggers.maxquerydepth;
Assert(afterTriggers.query_depth >= afterTriggers.maxquerydepth);
if (afterTriggers.maxquerydepth == 0)
{
int new_alloc = Max(afterTriggers.query_depth + 1, 8);
afterTriggers.query_stack = (AfterTriggersQueryData *)
MemoryContextAlloc(TopTransactionContext,
new_alloc * sizeof(AfterTriggersQueryData));
afterTriggers.maxquerydepth = new_alloc;
}
else
{
/* repalloc will keep the stack in the same context */
int old_alloc = afterTriggers.maxquerydepth;
int new_alloc = Max(afterTriggers.query_depth + 1,
old_alloc * 2);
afterTriggers.query_stack = (AfterTriggersQueryData *)
repalloc(afterTriggers.query_stack,
new_alloc * sizeof(AfterTriggersQueryData));
afterTriggers.maxquerydepth = new_alloc;
}
/* Initialize new array entries to empty */
while (init_depth < afterTriggers.maxquerydepth)
{
AfterTriggersQueryData *qs = &afterTriggers.query_stack[init_depth];
qs->events.head = NULL;
qs->events.tail = NULL;
qs->events.tailfree = NULL;
qs->fdw_tuplestore = NULL;
qs->tables = NIL;
++init_depth;
}
}
/*
* Create an empty SetConstraintState with room for numalloc trigstates
*/
static SetConstraintState
SetConstraintStateCreate(int numalloc)
{
SetConstraintState state;
/* Behave sanely with numalloc == 0 */
if (numalloc <= 0)
numalloc = 1;
/*
* We assume that zeroing will correctly initialize the state values.
*/
state = (SetConstraintState)
MemoryContextAllocZero(TopTransactionContext,
offsetof(SetConstraintStateData, trigstates) +
numalloc * sizeof(SetConstraintTriggerData));
state->numalloc = numalloc;
return state;
}
/*
* Copy a SetConstraintState
*/
static SetConstraintState
SetConstraintStateCopy(SetConstraintState origstate)
{
SetConstraintState state;
state = SetConstraintStateCreate(origstate->numstates);
state->all_isset = origstate->all_isset;
state->all_isdeferred = origstate->all_isdeferred;
state->numstates = origstate->numstates;
memcpy(state->trigstates, origstate->trigstates,
origstate->numstates * sizeof(SetConstraintTriggerData));
return state;
}
/*
* Add a per-trigger item to a SetConstraintState. Returns possibly-changed
* pointer to the state object (it will change if we have to repalloc).
*/
static SetConstraintState
SetConstraintStateAddItem(SetConstraintState state,
Oid tgoid, bool tgisdeferred)
{
if (state->numstates >= state->numalloc)
{
int newalloc = state->numalloc * 2;
newalloc = Max(newalloc, 8); /* in case original has size 0 */
state = (SetConstraintState)
repalloc(state,
offsetof(SetConstraintStateData, trigstates) +
newalloc * sizeof(SetConstraintTriggerData));
state->numalloc = newalloc;
Assert(state->numstates < state->numalloc);
}
state->trigstates[state->numstates].sct_tgoid = tgoid;
state->trigstates[state->numstates].sct_tgisdeferred = tgisdeferred;
state->numstates++;
return state;
}
/* ----------
* AfterTriggerSetState()
*
* Execute the SET CONSTRAINTS ... utility command.
* ----------
*/
void
AfterTriggerSetState(ConstraintsSetStmt *stmt)
{
int my_level = GetCurrentTransactionNestLevel();
/* If we haven't already done so, initialize our state. */
if (afterTriggers.state == NULL)
afterTriggers.state = SetConstraintStateCreate(8);
/*
* If in a subtransaction, and we didn't save the current state already,
* save it so it can be restored if the subtransaction aborts.
*/
if (my_level > 1 &&
afterTriggers.trans_stack[my_level].state == NULL)
{
afterTriggers.trans_stack[my_level].state =
SetConstraintStateCopy(afterTriggers.state);
}
/*
* Handle SET CONSTRAINTS ALL ...
*/
if (stmt->constraints == NIL)
{
/*
* Forget any previous SET CONSTRAINTS commands in this transaction.
*/
afterTriggers.state->numstates = 0;
/*
* Set the per-transaction ALL state to known.
*/
afterTriggers.state->all_isset = true;
afterTriggers.state->all_isdeferred = stmt->deferred;
}
else
{
Relation conrel;
Relation tgrel;
List *conoidlist = NIL;
List *tgoidlist = NIL;
ListCell *lc;
/*
* Handle SET CONSTRAINTS constraint-name [, ...]
*
* First, identify all the named constraints and make a list of their
* OIDs. Since, unlike the SQL spec, we allow multiple constraints of
* the same name within a schema, the specifications are not
* necessarily unique. Our strategy is to target all matching
* constraints within the first search-path schema that has any
* matches, but disregard matches in schemas beyond the first match.
* (This is a bit odd but it's the historical behavior.)
*
* A constraint in a partitioned table may have corresponding
* constraints in the partitions. Grab those too.
*/
conrel = table_open(ConstraintRelationId, AccessShareLock);
foreach(lc, stmt->constraints)
{
RangeVar *constraint = lfirst(lc);
bool found;
List *namespacelist;
ListCell *nslc;
if (constraint->catalogname)
{
if (strcmp(constraint->catalogname, get_database_name(MyDatabaseId)) != 0)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cross-database references are not implemented: \"%s.%s.%s\"",
constraint->catalogname, constraint->schemaname,
constraint->relname)));
}
/*
* If we're given the schema name with the constraint, look only
* in that schema. If given a bare constraint name, use the
* search path to find the first matching constraint.
*/
if (constraint->schemaname)
{
Oid namespaceId = LookupExplicitNamespace(constraint->schemaname,
false);
namespacelist = list_make1_oid(namespaceId);
}
else
{
namespacelist = fetch_search_path(true);
}
found = false;
foreach(nslc, namespacelist)
{
Oid namespaceId = lfirst_oid(nslc);
SysScanDesc conscan;
ScanKeyData skey[2];
HeapTuple tup;
ScanKeyInit(&skey[0],
Anum_pg_constraint_conname,
BTEqualStrategyNumber, F_NAMEEQ,
CStringGetDatum(constraint->relname));
ScanKeyInit(&skey[1],
Anum_pg_constraint_connamespace,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(namespaceId));
conscan = systable_beginscan(conrel, ConstraintNameNspIndexId,
true, NULL, 2, skey);
while (HeapTupleIsValid(tup = systable_getnext(conscan)))
{
Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tup);
if (con->condeferrable)
conoidlist = lappend_oid(conoidlist, con->oid);
else if (stmt->deferred)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("constraint \"%s\" is not deferrable",
constraint->relname)));
found = true;
}
systable_endscan(conscan);
/*
* Once we've found a matching constraint we do not search
* later parts of the search path.
*/
if (found)
break;
}
list_free(namespacelist);
/*
* Not found ?
*/
if (!found)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("constraint \"%s\" does not exist",
constraint->relname)));
}
/*
* Scan for any possible descendants of the constraints. We append
* whatever we find to the same list that we're scanning; this has the
* effect that we create new scans for those, too, so if there are
* further descendents, we'll also catch them.
*/
foreach(lc, conoidlist)
{
Oid parent = lfirst_oid(lc);
ScanKeyData key;
SysScanDesc scan;
HeapTuple tuple;
ScanKeyInit(&key,
Anum_pg_constraint_conparentid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(parent));
scan = systable_beginscan(conrel, ConstraintParentIndexId, true, NULL, 1, &key);
while (HeapTupleIsValid(tuple = systable_getnext(scan)))
{
Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tuple);
conoidlist = lappend_oid(conoidlist, con->oid);
}
systable_endscan(scan);
}
table_close(conrel, AccessShareLock);
/*
* Now, locate the trigger(s) implementing each of these constraints,
* and make a list of their OIDs.
*/
tgrel = table_open(TriggerRelationId, AccessShareLock);
foreach(lc, conoidlist)
{
Oid conoid = lfirst_oid(lc);
bool found;
ScanKeyData skey;
SysScanDesc tgscan;
HeapTuple htup;
found = false;
ScanKeyInit(&skey,
Anum_pg_trigger_tgconstraint,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(conoid));
tgscan = systable_beginscan(tgrel, TriggerConstraintIndexId, true,
NULL, 1, &skey);
while (HeapTupleIsValid(htup = systable_getnext(tgscan)))
{
Form_pg_trigger pg_trigger = (Form_pg_trigger) GETSTRUCT(htup);
/*
* Silently skip triggers that are marked as non-deferrable in
* pg_trigger. This is not an error condition, since a
* deferrable RI constraint may have some non-deferrable
* actions.
*/
if (pg_trigger->tgdeferrable)
tgoidlist = lappend_oid(tgoidlist, pg_trigger->oid);
found = true;
}
systable_endscan(tgscan);
/* Safety check: a deferrable constraint should have triggers */
if (!found)
elog(ERROR, "no triggers found for constraint with OID %u",
conoid);
}
table_close(tgrel, AccessShareLock);
/*
* Now we can set the trigger states of individual triggers for this
* xact.
*/
foreach(lc, tgoidlist)
{
Oid tgoid = lfirst_oid(lc);
SetConstraintState state = afterTriggers.state;
bool found = false;
int i;
for (i = 0; i < state->numstates; i++)
{
if (state->trigstates[i].sct_tgoid == tgoid)
{
state->trigstates[i].sct_tgisdeferred = stmt->deferred;
found = true;
break;
}
}
if (!found)
{
afterTriggers.state =
SetConstraintStateAddItem(state, tgoid, stmt->deferred);
}
}
}
/*
* SQL99 requires that when a constraint is set to IMMEDIATE, any deferred
* checks against that constraint must be made when the SET CONSTRAINTS
* command is executed -- i.e. the effects of the SET CONSTRAINTS command
* apply retroactively. We've updated the constraints state, so scan the
* list of previously deferred events to fire any that have now become
* immediate.
*
* Obviously, if this was SET ... DEFERRED then it can't have converted
* any unfired events to immediate, so we need do nothing in that case.
*/
if (!stmt->deferred)
{
AfterTriggerEventList *events = &afterTriggers.events;
bool snapshot_set = false;
while (afterTriggerMarkEvents(events, NULL, true))
{
CommandId firing_id = afterTriggers.firing_counter++;
/*
* Make sure a snapshot has been established in case trigger
* functions need one. Note that we avoid setting a snapshot if
* we don't find at least one trigger that has to be fired now.
* This is so that BEGIN; SET CONSTRAINTS ...; SET TRANSACTION
* ISOLATION LEVEL SERIALIZABLE; ... works properly. (If we are
* at the start of a transaction it's not possible for any trigger
* events to be queued yet.)
*/
if (!snapshot_set)
{
PushActiveSnapshot(GetTransactionSnapshot());
snapshot_set = true;
}
/*
* We can delete fired events if we are at top transaction level,
* but we'd better not if inside a subtransaction, since the
* subtransaction could later get rolled back.
*/
if (afterTriggerInvokeEvents(events, firing_id, NULL,
!IsSubTransaction()))
break; /* all fired */
}
if (snapshot_set)
PopActiveSnapshot();
}
else
{
/* no snapshot needed */
}
if (Gp_role == GP_ROLE_DISPATCH)
{
CdbDispatchUtilityStatement((Node *) stmt,
DF_CANCEL_ON_ERROR|
DF_NEED_TWO_PHASE,
NIL,
NULL);
}
}
/* ----------
* AfterTriggerPendingOnRel()
* Test to see if there are any pending after-trigger events for rel.
*
* This is used by TRUNCATE, CLUSTER, ALTER TABLE, etc to detect whether
* it is unsafe to perform major surgery on a relation. Note that only
* local pending events are examined. We assume that having exclusive lock
* on a rel guarantees there are no unserviced events in other backends ---
* but having a lock does not prevent there being such events in our own.
*
* In some scenarios it'd be reasonable to remove pending events (more
* specifically, mark them DONE by the current subxact) but without a lot
* of knowledge of the trigger semantics we can't do this in general.
* ----------
*/
bool
AfterTriggerPendingOnRel(Oid relid)
{
AfterTriggerEvent event;
AfterTriggerEventChunk *chunk;
int depth;
/* Scan queued events */
for_each_event_chunk(event, chunk, afterTriggers.events)
{
AfterTriggerShared evtshared = GetTriggerSharedData(event);
/*
* We can ignore completed events. (Even if a DONE flag is rolled
* back by subxact abort, it's OK because the effects of the TRUNCATE
* or whatever must get rolled back too.)
*/
if (event->ate_flags & AFTER_TRIGGER_DONE)
continue;
if (evtshared->ats_relid == relid)
return true;
}
/*
* Also scan events queued by incomplete queries. This could only matter
* if TRUNCATE/etc is executed by a function or trigger within an updating
* query on the same relation, which is pretty perverse, but let's check.
*/
for (depth = 0; depth <= afterTriggers.query_depth && depth < afterTriggers.maxquerydepth; depth++)
{
for_each_event_chunk(event, chunk, afterTriggers.query_stack[depth].events)
{
AfterTriggerShared evtshared = GetTriggerSharedData(event);
if (event->ate_flags & AFTER_TRIGGER_DONE)
continue;
if (evtshared->ats_relid == relid)
return true;
}
}
return false;
}
/* ----------
* AfterTriggerSaveEvent()
*
* Called by ExecA[RS]...Triggers() to queue up the triggers that should
* be fired for an event.
*
* NOTE: this is called whenever there are any triggers associated with
* the event (even if they are disabled). This function decides which
* triggers actually need to be queued. It is also called after each row,
* even if there are no triggers for that event, if there are any AFTER
* STATEMENT triggers for the statement which use transition tables, so that
* the transition tuplestores can be built. Furthermore, if the transition
* capture is happening for UPDATEd rows being moved to another partition due
* to the partition-key being changed, then this function is called once when
* the row is deleted (to capture OLD row), and once when the row is inserted
* into another partition (to capture NEW row). This is done separately because
* DELETE and INSERT happen on different tables.
*
* Transition tuplestores are built now, rather than when events are pulled
* off of the queue because AFTER ROW triggers are allowed to select from the
* transition tables for the statement.
* ----------
*/
static void
AfterTriggerSaveEvent(EState *estate, ResultRelInfo *relinfo,
int event, bool row_trigger,
TupleTableSlot *oldslot, TupleTableSlot *newslot,
List *recheckIndexes, Bitmapset *modifiedCols,
TransitionCaptureState *transition_capture)
{
Relation rel = relinfo->ri_RelationDesc;
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
AfterTriggerEventData new_event;
AfterTriggerSharedData new_shared;
char relkind = rel->rd_rel->relkind;
int tgtype_event;
int tgtype_level;
int i;
Tuplestorestate *fdw_tuplestore = NULL;
/*
* Check state. We use a normal test not Assert because it is possible to
* reach here in the wrong state given misconfigured RI triggers, in
* particular deferring a cascade action trigger.
*/
if (afterTriggers.query_depth < 0)
elog(ERROR, "AfterTriggerSaveEvent() called outside of query");
/* Don't fire statement-triggers in executor nodes. */
if (!row_trigger && Gp_role == GP_ROLE_EXECUTE)
return;
/* Be sure we have enough space to record events at this query depth. */
if (afterTriggers.query_depth >= afterTriggers.maxquerydepth)
AfterTriggerEnlargeQueryState();
/*
* If the directly named relation has any triggers with transition tables,
* then we need to capture transition tuples.
*/
if (row_trigger && transition_capture != NULL)
{
TupleTableSlot *original_insert_tuple = transition_capture->tcs_original_insert_tuple;
TupleConversionMap *map = transition_capture->tcs_map;
bool delete_old_table = transition_capture->tcs_delete_old_table;
bool update_old_table = transition_capture->tcs_update_old_table;
bool update_new_table = transition_capture->tcs_update_new_table;
bool insert_new_table = transition_capture->tcs_insert_new_table;
/*
* For INSERT events NEW should be non-NULL, for DELETE events OLD
* should be non-NULL, whereas for UPDATE events normally both OLD and
* NEW are non-NULL. But for UPDATE events fired for capturing
* transition tuples during UPDATE partition-key row movement, OLD is
* NULL when the event is for a row being inserted, whereas NEW is
* NULL when the event is for a row being deleted.
*/
Assert(!(event == TRIGGER_EVENT_DELETE && delete_old_table &&
TupIsNull(oldslot)));
Assert(!(event == TRIGGER_EVENT_INSERT && insert_new_table &&
TupIsNull(newslot)));
if (!TupIsNull(oldslot) &&
((event == TRIGGER_EVENT_DELETE && delete_old_table) ||
(event == TRIGGER_EVENT_UPDATE && update_old_table)))
{
Tuplestorestate *old_tuplestore;
old_tuplestore = transition_capture->tcs_private->old_tuplestore;
if (map != NULL)
{
TupleTableSlot *storeslot;
storeslot = transition_capture->tcs_private->storeslot;
if (!storeslot)
{
storeslot = ExecAllocTableSlot(&estate->es_tupleTable,
map->outdesc,
&TTSOpsVirtual);
transition_capture->tcs_private->storeslot = storeslot;
}
execute_attr_map_slot(map->attrMap, oldslot, storeslot);
tuplestore_puttupleslot(old_tuplestore, storeslot);
}
else
tuplestore_puttupleslot(old_tuplestore, oldslot);
}
if (!TupIsNull(newslot) &&
((event == TRIGGER_EVENT_INSERT && insert_new_table) ||
(event == TRIGGER_EVENT_UPDATE && update_new_table)))
{
Tuplestorestate *new_tuplestore;
new_tuplestore = transition_capture->tcs_private->new_tuplestore;
if (original_insert_tuple != NULL)
tuplestore_puttupleslot(new_tuplestore,
original_insert_tuple);
else if (map != NULL)
{
TupleTableSlot *storeslot;
storeslot = transition_capture->tcs_private->storeslot;
if (!storeslot)
{
storeslot = ExecAllocTableSlot(&estate->es_tupleTable,
map->outdesc,
&TTSOpsVirtual);
transition_capture->tcs_private->storeslot = storeslot;
}
execute_attr_map_slot(map->attrMap, newslot, storeslot);
tuplestore_puttupleslot(new_tuplestore, storeslot);
}
else
tuplestore_puttupleslot(new_tuplestore, newslot);
}
/*
* If transition tables are the only reason we're here, return. As
* mentioned above, we can also be here during update tuple routing in
* presence of transition tables, in which case this function is
* called separately for oldtup and newtup, so we expect exactly one
* of them to be NULL.
*/
if (trigdesc == NULL ||
(event == TRIGGER_EVENT_DELETE && !trigdesc->trig_delete_after_row) ||
(event == TRIGGER_EVENT_INSERT && !trigdesc->trig_insert_after_row) ||
(event == TRIGGER_EVENT_UPDATE && !trigdesc->trig_update_after_row) ||
(event == TRIGGER_EVENT_UPDATE && (TupIsNull(oldslot) ^ TupIsNull(newslot))))
return;
}
/*
* Validate the event code and collect the associated tuple CTIDs.
*
* The event code will be used both as a bitmask and an array offset, so
* validation is important to make sure we don't walk off the edge of our
* arrays.
*
* Also, if we're considering statement-level triggers, check whether we
* already queued a set of them for this event, and cancel the prior set
* if so. This preserves the behavior that statement-level triggers fire
* just once per statement and fire after row-level triggers.
*/
switch (event)
{
case TRIGGER_EVENT_INSERT:
tgtype_event = TRIGGER_TYPE_INSERT;
if (row_trigger)
{
Assert(oldslot == NULL);
Assert(newslot != NULL);
ItemPointerCopy(&(newslot->tts_tid), &(new_event.ate_ctid1));
ItemPointerSetInvalid(&(new_event.ate_ctid2));
}
else
{
Assert(oldslot == NULL);
Assert(newslot == NULL);
ItemPointerSetInvalid(&(new_event.ate_ctid1));
ItemPointerSetInvalid(&(new_event.ate_ctid2));
cancel_prior_stmt_triggers(RelationGetRelid(rel),
CMD_INSERT, event);
}
break;
case TRIGGER_EVENT_DELETE:
tgtype_event = TRIGGER_TYPE_DELETE;
if (row_trigger)
{
Assert(oldslot != NULL);
Assert(newslot == NULL);
ItemPointerCopy(&(oldslot->tts_tid), &(new_event.ate_ctid1));
ItemPointerSetInvalid(&(new_event.ate_ctid2));
}
else
{
Assert(oldslot == NULL);
Assert(newslot == NULL);
ItemPointerSetInvalid(&(new_event.ate_ctid1));
ItemPointerSetInvalid(&(new_event.ate_ctid2));
cancel_prior_stmt_triggers(RelationGetRelid(rel),
CMD_DELETE, event);
}
break;
case TRIGGER_EVENT_UPDATE:
tgtype_event = TRIGGER_TYPE_UPDATE;
if (row_trigger)
{
Assert(oldslot != NULL);
Assert(newslot != NULL);
ItemPointerCopy(&(oldslot->tts_tid), &(new_event.ate_ctid1));
ItemPointerCopy(&(newslot->tts_tid), &(new_event.ate_ctid2));
}
else
{
Assert(oldslot == NULL);
Assert(newslot == NULL);
ItemPointerSetInvalid(&(new_event.ate_ctid1));
ItemPointerSetInvalid(&(new_event.ate_ctid2));
cancel_prior_stmt_triggers(RelationGetRelid(rel),
CMD_UPDATE, event);
}
break;
case TRIGGER_EVENT_TRUNCATE:
tgtype_event = TRIGGER_TYPE_TRUNCATE;
Assert(oldslot == NULL);
Assert(newslot == NULL);
ItemPointerSetInvalid(&(new_event.ate_ctid1));
ItemPointerSetInvalid(&(new_event.ate_ctid2));
break;
default:
elog(ERROR, "invalid after-trigger event code: %d", event);
tgtype_event = 0; /* keep compiler quiet */
break;
}
if (!(relkind == RELKIND_FOREIGN_TABLE && row_trigger))
new_event.ate_flags = (row_trigger && event == TRIGGER_EVENT_UPDATE) ?
AFTER_TRIGGER_2CTID : AFTER_TRIGGER_1CTID;
/* else, we'll initialize ate_flags for each trigger */
tgtype_level = (row_trigger ? TRIGGER_TYPE_ROW : TRIGGER_TYPE_STATEMENT);
for (i = 0; i < trigdesc->numtriggers; i++)
{
Trigger *trigger = &trigdesc->triggers[i];
if (!TRIGGER_TYPE_MATCHES(trigger->tgtype,
tgtype_level,
TRIGGER_TYPE_AFTER,
tgtype_event))
continue;
if (!TriggerEnabled(estate, relinfo, trigger, event,
modifiedCols, oldslot, newslot))
continue;
if (relkind == RELKIND_FOREIGN_TABLE && row_trigger)
{
if (fdw_tuplestore == NULL)
{
fdw_tuplestore = GetCurrentFDWTuplestore();
new_event.ate_flags = AFTER_TRIGGER_FDW_FETCH;
}
else
/* subsequent event for the same tuple */
new_event.ate_flags = AFTER_TRIGGER_FDW_REUSE;
}
/*
* If the trigger is a foreign key enforcement trigger, there are
* certain cases where we can skip queueing the event because we can
* tell by inspection that the FK constraint will still pass.
*/
if (TRIGGER_FIRED_BY_UPDATE(event) || TRIGGER_FIRED_BY_DELETE(event))
{
switch (RI_FKey_trigger_type(trigger->tgfoid))
{
case RI_TRIGGER_PK:
/* Update or delete on trigger's PK table */
if (!RI_FKey_pk_upd_check_required(trigger, rel,
oldslot, newslot))
{
/* skip queuing this event */
continue;
}
break;
case RI_TRIGGER_FK:
/* Update on trigger's FK table */
if (!RI_FKey_fk_upd_check_required(trigger, rel,
oldslot, newslot))
{
/* skip queuing this event */
continue;
}
break;
case RI_TRIGGER_NONE:
/* Not an FK trigger */
break;
}
}
/*
* If the trigger is a deferred unique constraint check trigger, only
* queue it if the unique constraint was potentially violated, which
* we know from index insertion time.
*/
if (trigger->tgfoid == F_UNIQUE_KEY_RECHECK)
{
if (!list_member_oid(recheckIndexes, trigger->tgconstrindid))
continue; /* Uniqueness definitely not violated */
}
/*
* Fill in event structure and add it to the current query's queue.
* Note we set ats_table to NULL whenever this trigger doesn't use
* transition tables, to improve sharability of the shared event data.
*/
new_shared.ats_event =
(event & TRIGGER_EVENT_OPMASK) |
(row_trigger ? TRIGGER_EVENT_ROW : 0) |
(trigger->tgdeferrable ? AFTER_TRIGGER_DEFERRABLE : 0) |
(trigger->tginitdeferred ? AFTER_TRIGGER_INITDEFERRED : 0);
new_shared.ats_tgoid = trigger->tgoid;
new_shared.ats_relid = RelationGetRelid(rel);
new_shared.ats_firing_id = 0;
if ((trigger->tgoldtable || trigger->tgnewtable) &&
transition_capture != NULL)
new_shared.ats_table = transition_capture->tcs_private;
else
new_shared.ats_table = NULL;
afterTriggerAddEvent(&afterTriggers.query_stack[afterTriggers.query_depth].events,
&new_event, &new_shared);
}
/*
* Finally, spool any foreign tuple(s). The tuplestore squashes them to
* minimal tuples, so this loses any system columns. The executor lost
* those columns before us, for an unrelated reason, so this is fine.
*/
if (fdw_tuplestore)
{
if (oldslot != NULL)
tuplestore_puttupleslot(fdw_tuplestore, oldslot);
if (newslot != NULL)
tuplestore_puttupleslot(fdw_tuplestore, newslot);
}
}
/*
* Detect whether we already queued BEFORE STATEMENT triggers for the given
* relation + operation, and set the flag so the next call will report "true".
*/
static bool
before_stmt_triggers_fired(Oid relid, CmdType cmdType)
{
bool result;
AfterTriggersTableData *table;
/* Check state, like AfterTriggerSaveEvent. */
if (afterTriggers.query_depth < 0)
elog(ERROR, "before_stmt_triggers_fired() called outside of query");
/* Be sure we have enough space to record events at this query depth. */
if (afterTriggers.query_depth >= afterTriggers.maxquerydepth)
AfterTriggerEnlargeQueryState();
/*
* We keep this state in the AfterTriggersTableData that also holds
* transition tables for the relation + operation. In this way, if we are
* forced to make a new set of transition tables because more tuples get
* entered after we've already fired triggers, we will allow a new set of
* statement triggers to get queued.
*/
table = GetAfterTriggersTableData(relid, cmdType);
result = table->before_trig_done;
table->before_trig_done = true;
return result;
}
/*
* If we previously queued a set of AFTER STATEMENT triggers for the given
* relation + operation, and they've not been fired yet, cancel them. The
* caller will queue a fresh set that's after any row-level triggers that may
* have been queued by the current sub-statement, preserving (as much as
* possible) the property that AFTER ROW triggers fire before AFTER STATEMENT
* triggers, and that the latter only fire once. This deals with the
* situation where several FK enforcement triggers sequentially queue triggers
* for the same table into the same trigger query level. We can't fully
* prevent odd behavior though: if there are AFTER ROW triggers taking
* transition tables, we don't want to change the transition tables once the
* first such trigger has seen them. In such a case, any additional events
* will result in creating new transition tables and allowing new firings of
* statement triggers.
*
* This also saves the current event list location so that a later invocation
* of this function can cheaply find the triggers we're about to queue and
* cancel them.
*/
static void
cancel_prior_stmt_triggers(Oid relid, CmdType cmdType, int tgevent)
{
AfterTriggersTableData *table;
AfterTriggersQueryData *qs = &afterTriggers.query_stack[afterTriggers.query_depth];
/*
* We keep this state in the AfterTriggersTableData that also holds
* transition tables for the relation + operation. In this way, if we are
* forced to make a new set of transition tables because more tuples get
* entered after we've already fired triggers, we will allow a new set of
* statement triggers to get queued without canceling the old ones.
*/
table = GetAfterTriggersTableData(relid, cmdType);
if (table->after_trig_done)
{
/*
* We want to start scanning from the tail location that existed just
* before we inserted any statement triggers. But the events list
* might've been entirely empty then, in which case scan from the
* current head.
*/
AfterTriggerEvent event;
AfterTriggerEventChunk *chunk;
if (table->after_trig_events.tail)
{
chunk = table->after_trig_events.tail;
event = (AfterTriggerEvent) table->after_trig_events.tailfree;
}
else
{
chunk = qs->events.head;
event = NULL;
}
for_each_chunk_from(chunk)
{
if (event == NULL)
event = (AfterTriggerEvent) CHUNK_DATA_START(chunk);
for_each_event_from(event, chunk)
{
AfterTriggerShared evtshared = GetTriggerSharedData(event);
/*
* Exit loop when we reach events that aren't AS triggers for
* the target relation.
*/
if (evtshared->ats_relid != relid)
goto done;
if ((evtshared->ats_event & TRIGGER_EVENT_OPMASK) != tgevent)
goto done;
if (!TRIGGER_FIRED_FOR_STATEMENT(evtshared->ats_event))
goto done;
if (!TRIGGER_FIRED_AFTER(evtshared->ats_event))
goto done;
/* OK, mark it DONE */
event->ate_flags &= ~AFTER_TRIGGER_IN_PROGRESS;
event->ate_flags |= AFTER_TRIGGER_DONE;
}
/* signal we must reinitialize event ptr for next chunk */
event = NULL;
}
}
done:
/* In any case, save current insertion point for next time */
table->after_trig_done = true;
table->after_trig_events = qs->events;
}
/*
* SQL function pg_trigger_depth()
*/
Datum
pg_trigger_depth(PG_FUNCTION_ARGS)
{
PG_RETURN_INT32(MyTriggerDepth);
}
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