* INTERFACE ROUTINES
* ExecutorStart()
* ExecutorRun()
+ * ExecutorFinish()
* ExecutorEnd()
*
- * The old ExecutorMain() has been replaced by ExecutorStart(),
- * ExecutorRun() and ExecutorEnd()
- *
- * These three procedures are the external interfaces to the executor.
+ * These four procedures are the external interface to the executor.
* In each case, the query descriptor is required as an argument.
*
- * ExecutorStart() must be called at the beginning of execution of any
- * query plan and ExecutorEnd() should always be called at the end of
- * execution of a plan.
+ * ExecutorStart must be called at the beginning of execution of any
+ * query plan and ExecutorEnd must always be called at the end of
+ * execution of a plan (unless it is aborted due to error).
*
* ExecutorRun accepts direction and count arguments that specify whether
* the plan is to be executed forwards, backwards, and for how many tuples.
+ * In some cases ExecutorRun may be called multiple times to process all
+ * the tuples for a plan. It is also acceptable to stop short of executing
+ * the whole plan (but only if it is a SELECT).
+ *
+ * ExecutorFinish must be called after the final ExecutorRun call and
+ * before ExecutorEnd. This can be omitted only in case of EXPLAIN,
+ * which should also omit ExecutorRun.
*
* Portions Copyright (c) 1996-2011, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
#include "utils/tqual.h"
-/* Hooks for plugins to get control in ExecutorStart/Run/End() */
+/* Hooks for plugins to get control in ExecutorStart/Run/Finish/End */
ExecutorStart_hook_type ExecutorStart_hook = NULL;
ExecutorRun_hook_type ExecutorRun_hook = NULL;
+ExecutorFinish_hook_type ExecutorFinish_hook = NULL;
ExecutorEnd_hook_type ExecutorEnd_hook = NULL;
/* Hook for plugin to get control in ExecCheckRTPerms() */
/* decls for local routines only used within this module */
static void InitPlan(QueryDesc *queryDesc, int eflags);
+static void CheckValidRowMarkRel(Relation rel, RowMarkType markType);
+static void ExecPostprocessPlan(EState *estate);
static void ExecEndPlan(PlanState *planstate, EState *estate);
static void ExecutePlan(EState *estate, PlanState *planstate,
CmdType operation,
* This routine must be called at the beginning of any execution of any
* query plan
*
- * Takes a QueryDesc previously created by CreateQueryDesc (it's not real
- * clear why we bother to separate the two functions, but...). The tupDesc
+ * Takes a QueryDesc previously created by CreateQueryDesc (which is separate
+ * only because some places use QueryDescs for utility commands). The tupDesc
* field of the QueryDesc is filled in to describe the tuples that will be
* returned, and the internal fields (estate and planstate) are set up.
*
switch (queryDesc->operation)
{
case CMD_SELECT:
- /* SELECT INTO and SELECT FOR UPDATE/SHARE need to mark tuples */
+
+ /*
+ * SELECT INTO, SELECT FOR UPDATE/SHARE and modifying CTEs need to
+ * mark tuples
+ */
if (queryDesc->plannedstmt->intoClause != NULL ||
- queryDesc->plannedstmt->rowMarks != NIL)
+ queryDesc->plannedstmt->rowMarks != NIL ||
+ queryDesc->plannedstmt->hasModifyingCTE)
estate->es_output_cid = GetCurrentCommandId(true);
+
+ /*
+ * A SELECT without modifying CTEs can't possibly queue triggers,
+ * so force skip-triggers mode. This is just a marginal efficiency
+ * hack, since AfterTriggerBeginQuery/AfterTriggerEndQuery aren't
+ * all that expensive, but we might as well do it.
+ */
+ if (!queryDesc->plannedstmt->hasModifyingCTE)
+ eflags |= EXEC_FLAG_SKIP_TRIGGERS;
break;
case CMD_INSERT:
*/
estate->es_snapshot = RegisterSnapshot(queryDesc->snapshot);
estate->es_crosscheck_snapshot = RegisterSnapshot(queryDesc->crosscheck_snapshot);
+ estate->es_top_eflags = eflags;
estate->es_instrument = queryDesc->instrument_options;
/*
*/
InitPlan(queryDesc, eflags);
+ /*
+ * Set up an AFTER-trigger statement context, unless told not to, or
+ * unless it's EXPLAIN-only mode (when ExecutorFinish won't be called).
+ */
+ if (!(eflags & (EXEC_FLAG_SKIP_TRIGGERS | EXEC_FLAG_EXPLAIN_ONLY)))
+ AfterTriggerBeginQuery();
+
MemoryContextSwitchTo(oldcontext);
}
estate = queryDesc->estate;
Assert(estate != NULL);
+ Assert(!(estate->es_top_eflags & EXEC_FLAG_EXPLAIN_ONLY));
/*
* Switch into per-query memory context
*/
oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
- /* Allow instrumentation of ExecutorRun overall runtime */
+ /* Allow instrumentation of Executor overall runtime */
if (queryDesc->totaltime)
InstrStartNode(queryDesc->totaltime);
}
/* ----------------------------------------------------------------
+ * ExecutorFinish
+ *
+ * This routine must be called after the last ExecutorRun call.
+ * It performs cleanup such as firing AFTER triggers. It is
+ * separate from ExecutorEnd because EXPLAIN ANALYZE needs to
+ * include these actions in the total runtime.
+ *
+ * We provide a function hook variable that lets loadable plugins
+ * get control when ExecutorFinish is called. Such a plugin would
+ * normally call standard_ExecutorFinish().
+ *
+ * ----------------------------------------------------------------
+ */
+void
+ExecutorFinish(QueryDesc *queryDesc)
+{
+ if (ExecutorFinish_hook)
+ (*ExecutorFinish_hook) (queryDesc);
+ else
+ standard_ExecutorFinish(queryDesc);
+}
+
+void
+standard_ExecutorFinish(QueryDesc *queryDesc)
+{
+ EState *estate;
+ MemoryContext oldcontext;
+
+ /* sanity checks */
+ Assert(queryDesc != NULL);
+
+ estate = queryDesc->estate;
+
+ Assert(estate != NULL);
+ Assert(!(estate->es_top_eflags & EXEC_FLAG_EXPLAIN_ONLY));
+
+ /* This should be run once and only once per Executor instance */
+ Assert(!estate->es_finished);
+
+ /* Switch into per-query memory context */
+ oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
+
+ /* Allow instrumentation of Executor overall runtime */
+ if (queryDesc->totaltime)
+ InstrStartNode(queryDesc->totaltime);
+
+ /* Run ModifyTable nodes to completion */
+ ExecPostprocessPlan(estate);
+
+ /* Execute queued AFTER triggers, unless told not to */
+ if (!(estate->es_top_eflags & EXEC_FLAG_SKIP_TRIGGERS))
+ AfterTriggerEndQuery(estate);
+
+ if (queryDesc->totaltime)
+ InstrStopNode(queryDesc->totaltime, 0);
+
+ MemoryContextSwitchTo(oldcontext);
+
+ estate->es_finished = true;
+}
+
+/* ----------------------------------------------------------------
* ExecutorEnd
*
* This routine must be called at the end of execution of any
Assert(estate != NULL);
/*
+ * Check that ExecutorFinish was called, unless in EXPLAIN-only mode. This
+ * Assert is needed because ExecutorFinish is new as of 9.1, and callers
+ * might forget to call it.
+ */
+ Assert(estate->es_finished ||
+ (estate->es_top_eflags & EXEC_FLAG_EXPLAIN_ONLY));
+
+ /*
* Switch into per-query memory context to run ExecEndPlan
*/
oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
foreach(l, rangeTable)
{
- RangeTblEntry *rte = (RangeTblEntry *) lfirst(l);
+ RangeTblEntry *rte = (RangeTblEntry *) lfirst(l);
result = ExecCheckRTEPerms(rte);
if (!result)
}
if (ExecutorCheckPerms_hook)
- result = (*ExecutorCheckPerms_hook)(rangeTable,
- ereport_on_violation);
+ result = (*ExecutorCheckPerms_hook) (rangeTable,
+ ereport_on_violation);
return result;
}
InitResultRelInfo(resultRelInfo,
resultRelation,
resultRelationIndex,
- operation,
estate->es_instrument);
resultRelInfo++;
}
break;
}
- /* if foreign table, tuples can't be locked */
- if (relation && relation->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("SELECT FOR UPDATE/SHARE cannot be used with foreign table \"%s\"",
- RelationGetRelationName(relation))));
+ /* Check that relation is a legal target for marking */
+ if (relation)
+ CheckValidRowMarkRel(relation, rc->markType);
erm = (ExecRowMark *) palloc(sizeof(ExecRowMark));
erm->relation = relation;
}
/*
- * Initialize ResultRelInfo data for one result relation
+ * Check that a proposed result relation is a legal target for the operation
+ *
+ * In most cases parser and/or planner should have noticed this already, but
+ * let's make sure. In the view case we do need a test here, because if the
+ * view wasn't rewritten by a rule, it had better have an INSTEAD trigger.
+ *
+ * Note: when changing this function, you probably also need to look at
+ * CheckValidRowMarkRel.
*/
void
-InitResultRelInfo(ResultRelInfo *resultRelInfo,
- Relation resultRelationDesc,
- Index resultRelationIndex,
- CmdType operation,
- int instrument_options)
+CheckValidResultRel(Relation resultRel, CmdType operation)
{
- TriggerDesc *trigDesc = resultRelationDesc->trigdesc;
+ TriggerDesc *trigDesc = resultRel->trigdesc;
- /*
- * Check valid relkind ... in most cases parser and/or planner should have
- * noticed this already, but let's make sure. In the view case we do need
- * a test here, because if the view wasn't rewritten by a rule, it had
- * better have an INSTEAD trigger.
- */
- switch (resultRelationDesc->rd_rel->relkind)
+ switch (resultRel->rd_rel->relkind)
{
case RELKIND_RELATION:
/* OK */
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot change sequence \"%s\"",
- RelationGetRelationName(resultRelationDesc))));
+ RelationGetRelationName(resultRel))));
break;
case RELKIND_TOASTVALUE:
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot change TOAST relation \"%s\"",
- RelationGetRelationName(resultRelationDesc))));
+ RelationGetRelationName(resultRel))));
break;
case RELKIND_VIEW:
switch (operation)
case CMD_INSERT:
if (!trigDesc || !trigDesc->trig_insert_instead_row)
ereport(ERROR,
- (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
- errmsg("cannot insert into view \"%s\"",
- RelationGetRelationName(resultRelationDesc)),
- errhint("You need an unconditional ON INSERT DO INSTEAD rule or an INSTEAD OF INSERT trigger.")));
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("cannot insert into view \"%s\"",
+ RelationGetRelationName(resultRel)),
+ errhint("You need an unconditional ON INSERT DO INSTEAD rule or an INSTEAD OF INSERT trigger.")));
break;
case CMD_UPDATE:
if (!trigDesc || !trigDesc->trig_update_instead_row)
ereport(ERROR,
- (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
- errmsg("cannot update view \"%s\"",
- RelationGetRelationName(resultRelationDesc)),
- errhint("You need an unconditional ON UPDATE DO INSTEAD rule or an INSTEAD OF UPDATE trigger.")));
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("cannot update view \"%s\"",
+ RelationGetRelationName(resultRel)),
+ errhint("You need an unconditional ON UPDATE DO INSTEAD rule or an INSTEAD OF UPDATE trigger.")));
break;
case CMD_DELETE:
if (!trigDesc || !trigDesc->trig_delete_instead_row)
ereport(ERROR,
- (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
- errmsg("cannot delete from view \"%s\"",
- RelationGetRelationName(resultRelationDesc)),
- errhint("You need an unconditional ON DELETE DO INSTEAD rule or an INSTEAD OF DELETE trigger.")));
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("cannot delete from view \"%s\"",
+ RelationGetRelationName(resultRel)),
+ errhint("You need an unconditional ON DELETE DO INSTEAD rule or an INSTEAD OF DELETE trigger.")));
break;
default:
elog(ERROR, "unrecognized CmdType: %d", (int) operation);
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot change foreign table \"%s\"",
- RelationGetRelationName(resultRelationDesc))));
+ RelationGetRelationName(resultRel))));
break;
default:
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot change relation \"%s\"",
- RelationGetRelationName(resultRelationDesc))));
+ RelationGetRelationName(resultRel))));
break;
}
+}
- /* OK, fill in the node */
+/*
+ * Check that a proposed rowmark target relation is a legal target
+ *
+ * In most cases parser and/or planner should have noticed this already, but
+ * they don't cover all cases.
+ */
+static void
+CheckValidRowMarkRel(Relation rel, RowMarkType markType)
+{
+ switch (rel->rd_rel->relkind)
+ {
+ case RELKIND_RELATION:
+ /* OK */
+ break;
+ case RELKIND_SEQUENCE:
+ /* Must disallow this because we don't vacuum sequences */
+ ereport(ERROR,
+ (errcode(ERRCODE_WRONG_OBJECT_TYPE),
+ errmsg("cannot lock rows in sequence \"%s\"",
+ RelationGetRelationName(rel))));
+ break;
+ case RELKIND_TOASTVALUE:
+ /* We could allow this, but there seems no good reason to */
+ ereport(ERROR,
+ (errcode(ERRCODE_WRONG_OBJECT_TYPE),
+ errmsg("cannot lock rows in TOAST relation \"%s\"",
+ RelationGetRelationName(rel))));
+ break;
+ case RELKIND_VIEW:
+ /* Should not get here */
+ ereport(ERROR,
+ (errcode(ERRCODE_WRONG_OBJECT_TYPE),
+ errmsg("cannot lock rows in view \"%s\"",
+ RelationGetRelationName(rel))));
+ break;
+ case RELKIND_FOREIGN_TABLE:
+ /* Perhaps we can support this someday, but not today */
+ ereport(ERROR,
+ (errcode(ERRCODE_WRONG_OBJECT_TYPE),
+ errmsg("cannot lock rows in foreign table \"%s\"",
+ RelationGetRelationName(rel))));
+ break;
+ default:
+ ereport(ERROR,
+ (errcode(ERRCODE_WRONG_OBJECT_TYPE),
+ errmsg("cannot lock rows in relation \"%s\"",
+ RelationGetRelationName(rel))));
+ break;
+ }
+}
+
+/*
+ * Initialize ResultRelInfo data for one result relation
+ *
+ * Caution: before Postgres 9.1, this function included the relkind checking
+ * that's now in CheckValidResultRel, and it also did ExecOpenIndices if
+ * appropriate. Be sure callers cover those needs.
+ */
+void
+InitResultRelInfo(ResultRelInfo *resultRelInfo,
+ Relation resultRelationDesc,
+ Index resultRelationIndex,
+ int instrument_options)
+{
MemSet(resultRelInfo, 0, sizeof(ResultRelInfo));
resultRelInfo->type = T_ResultRelInfo;
resultRelInfo->ri_RangeTableIndex = resultRelationIndex;
resultRelInfo->ri_IndexRelationDescs = NULL;
resultRelInfo->ri_IndexRelationInfo = NULL;
/* make a copy so as not to depend on relcache info not changing... */
- resultRelInfo->ri_TrigDesc = CopyTriggerDesc(trigDesc);
+ resultRelInfo->ri_TrigDesc = CopyTriggerDesc(resultRelationDesc->trigdesc);
if (resultRelInfo->ri_TrigDesc)
{
int n = resultRelInfo->ri_TrigDesc->numtriggers;
resultRelInfo->ri_ConstraintExprs = NULL;
resultRelInfo->ri_junkFilter = NULL;
resultRelInfo->ri_projectReturning = NULL;
-
- /*
- * If there are indices on the result relation, open them and save
- * descriptors in the result relation info, so that we can add new index
- * entries for the tuples we add/update. We need not do this for a
- * DELETE, however, since deletion doesn't affect indexes.
- */
- if (resultRelationDesc->rd_rel->relhasindex &&
- operation != CMD_DELETE)
- ExecOpenIndices(resultRelInfo);
}
/*
/*
* Open the target relation's relcache entry. We assume that an
* appropriate lock is still held by the backend from whenever the trigger
- * event got queued, so we need take no new lock here.
+ * event got queued, so we need take no new lock here. Also, we need not
+ * recheck the relkind, so no need for CheckValidResultRel.
*/
rel = heap_open(relid, NoLock);
/*
- * Make the new entry in the right context. Currently, we don't need any
- * index information in ResultRelInfos used only for triggers, so tell
- * InitResultRelInfo it's a DELETE.
+ * Make the new entry in the right context.
*/
oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
rInfo = makeNode(ResultRelInfo);
InitResultRelInfo(rInfo,
rel,
0, /* dummy rangetable index */
- CMD_DELETE,
estate->es_instrument);
estate->es_trig_target_relations =
lappend(estate->es_trig_target_relations, rInfo);
MemoryContextSwitchTo(oldcontext);
+ /*
+ * Currently, we don't need any index information in ResultRelInfos used
+ * only for triggers, so no need to call ExecOpenIndices.
+ */
+
return rInfo;
}
}
/* ----------------------------------------------------------------
+ * ExecPostprocessPlan
+ *
+ * Give plan nodes a final chance to execute before shutdown
+ * ----------------------------------------------------------------
+ */
+static void
+ExecPostprocessPlan(EState *estate)
+{
+ ListCell *lc;
+
+ /*
+ * Make sure nodes run forward.
+ */
+ estate->es_direction = ForwardScanDirection;
+
+ /*
+ * Run any secondary ModifyTable nodes to completion, in case the main
+ * query did not fetch all rows from them. (We do this to ensure that
+ * such nodes have predictable results.)
+ */
+ foreach(lc, estate->es_auxmodifytables)
+ {
+ PlanState *ps = (PlanState *) lfirst(lc);
+
+ for (;;)
+ {
+ TupleTableSlot *slot;
+
+ /* Reset the per-output-tuple exprcontext each time */
+ ResetPerTupleExprContext(estate);
+
+ slot = ExecProcNode(ps);
+
+ if (TupIsNull(slot))
+ break;
+ }
+ }
+}
+
+/* ----------------------------------------------------------------
* ExecEndPlan
*
* Cleans up the query plan -- closes files and frees up storage
estate->es_result_relation_info = parentestate->es_result_relation_info;
/* es_trig_target_relations must NOT be copied */
estate->es_rowMarks = parentestate->es_rowMarks;
+ estate->es_top_eflags = parentestate->es_top_eflags;
estate->es_instrument = parentestate->es_instrument;
estate->es_select_into = parentestate->es_select_into;
estate->es_into_oids = parentestate->es_into_oids;
+ /* es_auxmodifytables must NOT be copied */
/*
* The external param list is simply shared from parent. The internal
* ExecInitSubPlan expects to be able to find these entries. Some of the
* SubPlans might not be used in the part of the plan tree we intend to
* run, but since it's not easy to tell which, we just initialize them
- * all.
+ * all. (However, if the subplan is headed by a ModifyTable node, then it
+ * must be a data-modifying CTE, which we will certainly not need to
+ * re-run, so we can skip initializing it. This is just an efficiency
+ * hack; it won't skip data-modifying CTEs for which the ModifyTable node
+ * is not at the top.)
*/
Assert(estate->es_subplanstates == NIL);
foreach(l, parentestate->es_plannedstmt->subplans)
Plan *subplan = (Plan *) lfirst(l);
PlanState *subplanstate;
- subplanstate = ExecInitNode(subplan, estate, 0);
+ /* Don't initialize ModifyTable subplans, per comment above */
+ if (IsA(subplan, ModifyTable))
+ subplanstate = NULL;
+ else
+ subplanstate = ExecInitNode(subplan, estate, 0);
estate->es_subplanstates = lappend(estate->es_subplanstates,
subplanstate);
Oid namespaceId;
Oid tablespaceId;
Datum reloptions;
- AclResult aclresult;
Oid intoRelationId;
- TupleDesc tupdesc;
DR_intorel *myState;
static char *validnsps[] = HEAP_RELOPT_NAMESPACES;
errmsg("ON COMMIT can only be used on temporary tables")));
/*
+ * Find namespace to create in, check its permissions
+ */
+ intoName = into->rel->relname;
+ namespaceId = RangeVarGetAndCheckCreationNamespace(into->rel);
+ RangeVarAdjustRelationPersistence(into->rel, namespaceId);
+
+ /*
* Security check: disallow creating temp tables from security-restricted
* code. This is needed because calling code might not expect untrusted
* tables to appear in pg_temp at the front of its search path.
errmsg("cannot create temporary table within security-restricted operation")));
/*
- * Find namespace to create in, check its permissions
- */
- intoName = into->rel->relname;
- namespaceId = RangeVarGetCreationNamespace(into->rel);
-
- aclresult = pg_namespace_aclcheck(namespaceId, GetUserId(),
- ACL_CREATE);
- if (aclresult != ACLCHECK_OK)
- aclcheck_error(aclresult, ACL_KIND_NAMESPACE,
- get_namespace_name(namespaceId));
-
- /*
* Select tablespace to use. If not specified, use default tablespace
* (which may in turn default to database's default).
*/
false);
(void) heap_reloptions(RELKIND_RELATION, reloptions, true);
- /* Copy the tupdesc because heap_create_with_catalog modifies it */
- tupdesc = CreateTupleDescCopy(queryDesc->tupDesc);
-
/* Now we can actually create the new relation */
intoRelationId = heap_create_with_catalog(intoName,
namespaceId,
InvalidOid,
InvalidOid,
GetUserId(),
- tupdesc,
+ queryDesc->tupDesc,
NIL,
RELKIND_RELATION,
into->rel->relpersistence,
into->onCommit,
reloptions,
true,
- allowSystemTableMods,
- false);
+ allowSystemTableMods);
Assert(intoRelationId != InvalidOid);
- FreeTupleDesc(tupdesc);
-
/*
* Advance command counter so that the newly-created relation's catalog
* tuples will be visible to heap_open.
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