* 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 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) 1996-2012, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
*/
#include "postgres.h"
-#include "access/reloptions.h"
+#include "access/htup_details.h"
#include "access/sysattr.h"
#include "access/transam.h"
#include "access/xact.h"
-#include "catalog/heap.h"
#include "catalog/namespace.h"
-#include "catalog/toasting.h"
-#include "commands/tablespace.h"
+#include "commands/matview.h"
#include "commands/trigger.h"
#include "executor/execdebug.h"
+#include "foreign/fdwapi.h"
#include "mb/pg_wchar.h"
#include "miscadmin.h"
#include "optimizer/clauses.h"
-#include "parser/parse_clause.h"
#include "parser/parsetree.h"
#include "storage/bufmgr.h"
#include "storage/lmgr.h"
-#include "storage/smgr.h"
#include "tcop/utility.h"
#include "utils/acl.h"
-#include "utils/builtins.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
+#include "utils/rls.h"
#include "utils/snapmgr.h"
#include "utils/tqual.h"
ScanDirection direction,
DestReceiver *dest);
static bool ExecCheckRTEPerms(RangeTblEntry *rte);
+static bool ExecCheckRTEPermsModified(Oid relOid, Oid userid,
+ Bitmapset *modifiedCols,
+ AclMode requiredPerms);
static void ExecCheckXactReadOnly(PlannedStmt *plannedstmt);
-static char *ExecBuildSlotValueDescription(TupleTableSlot *slot,
- int maxfieldlen);
+static char *ExecBuildSlotValueDescription(Oid reloid,
+ TupleTableSlot *slot,
+ TupleDesc tupdesc,
+ Bitmapset *modifiedCols,
+ int maxfieldlen);
static void EvalPlanQualStart(EPQState *epqstate, EState *parentestate,
Plan *planTree);
-static void OpenIntoRel(QueryDesc *queryDesc);
-static void CloseIntoRel(QueryDesc *queryDesc);
-static void intorel_startup(DestReceiver *self, int operation, TupleDesc typeinfo);
-static void intorel_receive(TupleTableSlot *slot, DestReceiver *self);
-static void intorel_shutdown(DestReceiver *self);
-static void intorel_destroy(DestReceiver *self);
+
+/*
+ * Note that GetUpdatedColumns() also exists in commands/trigger.c. There does
+ * not appear to be any good header to put it into, given the structures that
+ * it uses, so we let them be duplicated. Be sure to update both if one needs
+ * to be changed, however.
+ */
+#define GetInsertedColumns(relinfo, estate) \
+ (rt_fetch((relinfo)->ri_RangeTableIndex, (estate)->es_range_table)->insertedCols)
+#define GetUpdatedColumns(relinfo, estate) \
+ (rt_fetch((relinfo)->ri_RangeTableIndex, (estate)->es_range_table)->updatedCols)
/* end of local decls */
/*
* If the transaction is read-only, we need to check if any writes are
* planned to non-temporary tables. EXPLAIN is considered read-only.
+ *
+ * Don't allow writes in parallel mode. Supporting UPDATE and DELETE
+ * would require (a) storing the combocid hash in shared memory, rather
+ * than synchronizing it just once at the start of parallelism, and (b) an
+ * alternative to heap_update()'s reliance on xmax for mutual exclusion.
+ * INSERT may have no such troubles, but we forbid it to simplify the
+ * checks.
+ *
+ * We have lower-level defenses in CommandCounterIncrement and elsewhere
+ * against performing unsafe operations in parallel mode, but this gives a
+ * more user-friendly error message.
*/
- if (XactReadOnly && !(eflags & EXEC_FLAG_EXPLAIN_ONLY))
+ if ((XactReadOnly || IsInParallelMode()) &&
+ !(eflags & EXEC_FLAG_EXPLAIN_ONLY))
ExecCheckXactReadOnly(queryDesc->plannedstmt);
/*
case CMD_SELECT:
/*
- * SELECT INTO, SELECT FOR UPDATE/SHARE and modifying CTEs need to
- * mark tuples
+ * SELECT FOR [KEY] UPDATE/SHARE and modifying CTEs need to mark
+ * tuples
*/
- if (queryDesc->plannedstmt->intoClause != NULL ||
- queryDesc->plannedstmt->rowMarks != NIL ||
+ if (queryDesc->plannedstmt->rowMarks != NIL ||
queryDesc->plannedstmt->hasModifyingCTE)
estate->es_output_cid = GetCurrentCommandId(true);
if (!(eflags & (EXEC_FLAG_SKIP_TRIGGERS | EXEC_FLAG_EXPLAIN_ONLY)))
AfterTriggerBeginQuery();
+ /* Enter parallel mode, if required by the query. */
+ if (queryDesc->plannedstmt->parallelModeNeeded &&
+ !(eflags & EXEC_FLAG_EXPLAIN_ONLY))
+ EnterParallelMode();
+
MemoryContextSwitchTo(oldcontext);
}
* we retrieve up to 'count' tuples in the specified direction.
*
* Note: count = 0 is interpreted as no portal limit, i.e., run to
- * completion.
+ * completion. Also note that the count limit is only applied to
+ * retrieved tuples, not for instance to those inserted/updated/deleted
+ * by a ModifyTable plan node.
*
* There is no return value, but output tuples (if any) are sent to
* the destination receiver specified in the QueryDesc; and the number
if (sendTuples)
(*dest->rStartup) (dest, operation, queryDesc->tupDesc);
- /*
- * if it's CREATE TABLE AS ... WITH NO DATA, skip plan execution
- */
- if (estate->es_select_into &&
- queryDesc->plannedstmt->intoClause->skipData)
- direction = NoMovementScanDirection;
-
/*
* run plan
*/
direction,
dest);
+ /* Allow nodes to release or shut down resources. */
+ (void) ExecShutdownNode(queryDesc->planstate);
+
/*
* shutdown tuple receiver, if we started it
*/
* ExecutorFinish
*
* This routine must be called after the last ExecutorRun call.
- * It performs cleanup such as firing AFTER triggers. It is
+ * 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
+ * get control when ExecutorFinish is called. Such a plugin would
* normally call standard_ExecutorFinish().
*
* ----------------------------------------------------------------
ExecEndPlan(queryDesc->planstate, estate);
- /*
- * Close the SELECT INTO relation if any
- */
- if (estate->es_select_into)
- CloseIntoRel(queryDesc);
-
/* do away with our snapshots */
UnregisterSnapshot(estate->es_snapshot);
UnregisterSnapshot(estate->es_crosscheck_snapshot);
*/
MemoryContextSwitchTo(oldcontext);
+ /* Exit parallel mode, if it was required by the query. */
+ if (queryDesc->plannedstmt->parallelModeNeeded &&
+ !(estate->es_top_eflags & EXEC_FLAG_EXPLAIN_ONLY))
+ ExitParallelMode();
+
/*
* Release EState and per-query memory context. This should release
* everything the executor has allocated.
*
* Returns true if permissions are adequate. Otherwise, throws an appropriate
* error if ereport_on_violation is true, or simply returns false otherwise.
+ *
+ * Note that this does NOT address row level security policies (aka: RLS). If
+ * rows will be returned to the user as a result of this permission check
+ * passing, then RLS also needs to be consulted (and check_enable_rls()).
+ *
+ * See rewrite/rowsecurity.c.
*/
bool
ExecCheckRTPerms(List *rangeTable, bool ereport_on_violation)
AclMode remainingPerms;
Oid relOid;
Oid userid;
- Bitmapset *tmpset;
- int col;
/*
* Only plain-relation RTEs need to be checked here. Function RTEs are
* userid to check as: current user unless we have a setuid indication.
*
* Note: GetUserId() is presently fast enough that there's no harm in
- * calling it separately for each RTE. If that stops being true, we could
+ * calling it separately for each RTE. If that stops being true, we could
* call it once in ExecCheckRTPerms and pass the userid down from there.
* But for now, no need for the extra clutter.
*/
remainingPerms = requiredPerms & ~relPerms;
if (remainingPerms != 0)
{
+ int col = -1;
+
/*
* If we lack any permissions that exist only as relation permissions,
* we can fail straight away.
return false;
}
- tmpset = bms_copy(rte->selectedCols);
- while ((col = bms_first_member(tmpset)) >= 0)
+ while ((col = bms_next_member(rte->selectedCols, col)) >= 0)
{
- /* remove the column number offset */
- col += FirstLowInvalidHeapAttributeNumber;
- if (col == InvalidAttrNumber)
+ /* bit #s are offset by FirstLowInvalidHeapAttributeNumber */
+ AttrNumber attno = col + FirstLowInvalidHeapAttributeNumber;
+
+ if (attno == InvalidAttrNumber)
{
/* Whole-row reference, must have priv on all cols */
if (pg_attribute_aclcheck_all(relOid, userid, ACL_SELECT,
}
else
{
- if (pg_attribute_aclcheck(relOid, col, userid,
+ if (pg_attribute_aclcheck(relOid, attno, userid,
ACL_SELECT) != ACLCHECK_OK)
return false;
}
}
- bms_free(tmpset);
}
/*
- * Basically the same for the mod columns, with either INSERT or
- * UPDATE privilege as specified by remainingPerms.
+ * Basically the same for the mod columns, for both INSERT and UPDATE
+ * privilege as specified by remainingPerms.
*/
- remainingPerms &= ~ACL_SELECT;
- if (remainingPerms != 0)
- {
- /*
- * When the query doesn't explicitly change any columns, allow the
- * query if we have permission on any column of the rel. This is
- * to handle SELECT FOR UPDATE as well as possible corner cases in
- * INSERT and UPDATE.
- */
- if (bms_is_empty(rte->modifiedCols))
- {
- if (pg_attribute_aclcheck_all(relOid, userid, remainingPerms,
- ACLMASK_ANY) != ACLCHECK_OK)
- return false;
- }
+ if (remainingPerms & ACL_INSERT && !ExecCheckRTEPermsModified(relOid,
+ userid,
+ rte->insertedCols,
+ ACL_INSERT))
+ return false;
- tmpset = bms_copy(rte->modifiedCols);
- while ((col = bms_first_member(tmpset)) >= 0)
- {
- /* remove the column number offset */
- col += FirstLowInvalidHeapAttributeNumber;
- if (col == InvalidAttrNumber)
- {
- /* whole-row reference can't happen here */
- elog(ERROR, "whole-row update is not implemented");
- }
- else
- {
- if (pg_attribute_aclcheck(relOid, col, userid,
- remainingPerms) != ACLCHECK_OK)
- return false;
- }
- }
- bms_free(tmpset);
+ if (remainingPerms & ACL_UPDATE && !ExecCheckRTEPermsModified(relOid,
+ userid,
+ rte->updatedCols,
+ ACL_UPDATE))
+ return false;
+ }
+ return true;
+}
+
+/*
+ * ExecCheckRTEPermsModified
+ * Check INSERT or UPDATE access permissions for a single RTE (these
+ * are processed uniformly).
+ */
+static bool
+ExecCheckRTEPermsModified(Oid relOid, Oid userid, Bitmapset *modifiedCols,
+ AclMode requiredPerms)
+{
+ int col = -1;
+
+ /*
+ * When the query doesn't explicitly update any columns, allow the query
+ * if we have permission on any column of the rel. This is to handle
+ * SELECT FOR UPDATE as well as possible corner cases in UPDATE.
+ */
+ if (bms_is_empty(modifiedCols))
+ {
+ if (pg_attribute_aclcheck_all(relOid, userid, requiredPerms,
+ ACLMASK_ANY) != ACLCHECK_OK)
+ return false;
+ }
+
+ while ((col = bms_next_member(modifiedCols, col)) >= 0)
+ {
+ /* bit #s are offset by FirstLowInvalidHeapAttributeNumber */
+ AttrNumber attno = col + FirstLowInvalidHeapAttributeNumber;
+
+ if (attno == InvalidAttrNumber)
+ {
+ /* whole-row reference can't happen here */
+ elog(ERROR, "whole-row update is not implemented");
+ }
+ else
+ {
+ if (pg_attribute_aclcheck(relOid, attno, userid,
+ requiredPerms) != ACLCHECK_OK)
+ return false;
}
}
return true;
}
/*
- * Check that the query does not imply any writes to non-temp tables.
+ * Check that the query does not imply any writes to non-temp tables;
+ * unless we're in parallel mode, in which case don't even allow writes
+ * to temp tables.
*
* Note: in a Hot Standby slave this would need to reject writes to temp
- * tables as well; but an HS slave can't have created any temp tables
- * in the first place, so no need to check that.
+ * tables just as we do in parallel mode; but an HS slave can't have created
+ * any temp tables in the first place, so no need to check that.
*/
static void
ExecCheckXactReadOnly(PlannedStmt *plannedstmt)
ListCell *l;
/*
- * CREATE TABLE AS or SELECT INTO?
- *
- * XXX should we allow this if the destination is temp? Considering that
- * it would still require catalog changes, probably not.
+ * Fail if write permissions are requested in parallel mode for table
+ * (temp or non-temp), otherwise fail for any non-temp table.
*/
- if (plannedstmt->intoClause != NULL)
- PreventCommandIfReadOnly(CreateCommandTag((Node *) plannedstmt));
-
- /* Fail if write permissions are requested on any non-temp table */
foreach(l, plannedstmt->rtable)
{
RangeTblEntry *rte = (RangeTblEntry *) lfirst(l);
PreventCommandIfReadOnly(CreateCommandTag((Node *) plannedstmt));
}
+
+ if (plannedstmt->commandType != CMD_SELECT || plannedstmt->hasModifyingCTE)
+ PreventCommandIfParallelMode(CreateCommandTag((Node *) plannedstmt));
}
}
/*
- * Similarly, we have to lock relations selected FOR UPDATE/FOR SHARE
+ * Similarly, we have to lock relations selected FOR [KEY] UPDATE/SHARE
* before we initialize the plan tree, else we'd be risking lock upgrades.
* While we are at it, build the ExecRowMark list.
*/
if (rc->isParent)
continue;
+ /* get relation's OID (will produce InvalidOid if subquery) */
+ relid = getrelid(rc->rti, rangeTable);
+
+ /*
+ * If you change the conditions under which rel locks are acquired
+ * here, be sure to adjust ExecOpenScanRelation to match.
+ */
switch (rc->markType)
{
case ROW_MARK_EXCLUSIVE:
+ case ROW_MARK_NOKEYEXCLUSIVE:
case ROW_MARK_SHARE:
- relid = getrelid(rc->rti, rangeTable);
+ case ROW_MARK_KEYSHARE:
relation = heap_open(relid, RowShareLock);
break;
case ROW_MARK_REFERENCE:
- relid = getrelid(rc->rti, rangeTable);
relation = heap_open(relid, AccessShareLock);
break;
case ROW_MARK_COPY:
- /* there's no real table here ... */
+ /* no physical table access is required */
relation = NULL;
break;
default:
erm = (ExecRowMark *) palloc(sizeof(ExecRowMark));
erm->relation = relation;
+ erm->relid = relid;
erm->rti = rc->rti;
erm->prti = rc->prti;
erm->rowmarkId = rc->rowmarkId;
erm->markType = rc->markType;
- erm->noWait = rc->noWait;
+ erm->strength = rc->strength;
+ erm->waitPolicy = rc->waitPolicy;
+ erm->ermActive = false;
ItemPointerSetInvalid(&(erm->curCtid));
+ erm->ermExtra = NULL;
estate->es_rowMarks = lappend(estate->es_rowMarks, erm);
}
- /*
- * Detect whether we're doing SELECT INTO. If so, set the es_into_oids
- * flag appropriately so that the plan tree will be initialized with the
- * correct tuple descriptors. (Other SELECT INTO stuff comes later.)
- */
- estate->es_select_into = false;
- if (operation == CMD_SELECT && plannedstmt->intoClause != NULL)
- {
- estate->es_select_into = true;
- estate->es_into_oids = interpretOidsOption(plannedstmt->intoClause->options);
- }
-
/*
* Initialize the executor's tuple table to empty.
*/
* it is a parameterless subplan (not initplan), we suggest that it be
* prepared to handle REWIND efficiently; otherwise there is no need.
*/
- sp_eflags = eflags & EXEC_FLAG_EXPLAIN_ONLY;
+ sp_eflags = eflags
+ & (EXEC_FLAG_EXPLAIN_ONLY | EXEC_FLAG_WITH_NO_DATA);
if (bms_is_member(i, plannedstmt->rewindPlanIDs))
sp_eflags |= EXEC_FLAG_REWIND;
planstate = ExecInitNode(plan, estate, eflags);
/*
- * Get the tuple descriptor describing the type of tuples to return. (this
- * is especially important if we are creating a relation with "SELECT
- * INTO")
+ * Get the tuple descriptor describing the type of tuples to return.
*/
tupType = ExecGetResultType(planstate);
queryDesc->tupDesc = tupType;
queryDesc->planstate = planstate;
-
- /*
- * If doing SELECT INTO, initialize the "into" relation. We must wait
- * till now so we have the "clean" result tuple type to create the new
- * table from.
- *
- * If EXPLAIN, skip creating the "into" relation.
- */
- if (estate->es_select_into && !(eflags & EXEC_FLAG_EXPLAIN_ONLY))
- OpenIntoRel(queryDesc);
}
/*
* 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.
+ * Generally the parser and/or planner should have noticed any such mistake
+ * already, but let's make sure.
*
* Note: when changing this function, you probably also need to look at
* CheckValidRowMarkRel.
CheckValidResultRel(Relation resultRel, CmdType operation)
{
TriggerDesc *trigDesc = resultRel->trigdesc;
+ FdwRoutine *fdwroutine;
switch (resultRel->rd_rel->relkind)
{
RelationGetRelationName(resultRel))));
break;
case RELKIND_VIEW:
+
+ /*
+ * Okay only if there's a suitable INSTEAD OF trigger. Messages
+ * here should match rewriteHandler.c's rewriteTargetView, except
+ * that we omit errdetail because we haven't got the information
+ * handy (and given that we really shouldn't get here anyway, it's
+ * not worth great exertion to get).
+ */
switch (operation)
{
case CMD_INSERT:
(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.")));
+ errhint("To enable inserting into the view, provide an INSTEAD OF INSERT trigger or an unconditional ON INSERT DO INSTEAD rule.")));
break;
case CMD_UPDATE:
if (!trigDesc || !trigDesc->trig_update_instead_row)
(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.")));
+ errhint("To enable updating the view, provide an INSTEAD OF UPDATE trigger or an unconditional ON UPDATE DO INSTEAD rule.")));
break;
case CMD_DELETE:
if (!trigDesc || !trigDesc->trig_delete_instead_row)
(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.")));
+ errhint("To enable deleting from the view, provide an INSTEAD OF DELETE trigger or an unconditional ON DELETE DO INSTEAD rule.")));
break;
default:
elog(ERROR, "unrecognized CmdType: %d", (int) operation);
break;
}
break;
+ case RELKIND_MATVIEW:
+ if (!MatViewIncrementalMaintenanceIsEnabled())
+ ereport(ERROR,
+ (errcode(ERRCODE_WRONG_OBJECT_TYPE),
+ errmsg("cannot change materialized view \"%s\"",
+ RelationGetRelationName(resultRel))));
+ break;
case RELKIND_FOREIGN_TABLE:
- ereport(ERROR,
- (errcode(ERRCODE_WRONG_OBJECT_TYPE),
- errmsg("cannot change foreign table \"%s\"",
- RelationGetRelationName(resultRel))));
+ /* Okay only if the FDW supports it */
+ fdwroutine = GetFdwRoutineForRelation(resultRel, false);
+ switch (operation)
+ {
+ case CMD_INSERT:
+ if (fdwroutine->ExecForeignInsert == NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("cannot insert into foreign table \"%s\"",
+ RelationGetRelationName(resultRel))));
+ if (fdwroutine->IsForeignRelUpdatable != NULL &&
+ (fdwroutine->IsForeignRelUpdatable(resultRel) & (1 << CMD_INSERT)) == 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("foreign table \"%s\" does not allow inserts",
+ RelationGetRelationName(resultRel))));
+ break;
+ case CMD_UPDATE:
+ if (fdwroutine->ExecForeignUpdate == NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("cannot update foreign table \"%s\"",
+ RelationGetRelationName(resultRel))));
+ if (fdwroutine->IsForeignRelUpdatable != NULL &&
+ (fdwroutine->IsForeignRelUpdatable(resultRel) & (1 << CMD_UPDATE)) == 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("foreign table \"%s\" does not allow updates",
+ RelationGetRelationName(resultRel))));
+ break;
+ case CMD_DELETE:
+ if (fdwroutine->ExecForeignDelete == NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("cannot delete from foreign table \"%s\"",
+ RelationGetRelationName(resultRel))));
+ if (fdwroutine->IsForeignRelUpdatable != NULL &&
+ (fdwroutine->IsForeignRelUpdatable(resultRel) & (1 << CMD_DELETE)) == 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("foreign table \"%s\" does not allow deletes",
+ RelationGetRelationName(resultRel))));
+ break;
+ default:
+ elog(ERROR, "unrecognized CmdType: %d", (int) operation);
+ break;
+ }
break;
default:
ereport(ERROR,
static void
CheckValidRowMarkRel(Relation rel, RowMarkType markType)
{
+ FdwRoutine *fdwroutine;
+
switch (rel->rd_rel->relkind)
{
case RELKIND_RELATION:
RelationGetRelationName(rel))));
break;
case RELKIND_VIEW:
- /* Should not get here */
+ /* Should not get here; planner should have expanded the view */
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot lock rows in view \"%s\"",
RelationGetRelationName(rel))));
break;
+ case RELKIND_MATVIEW:
+ /* Allow referencing a matview, but not actual locking clauses */
+ if (markType != ROW_MARK_REFERENCE)
+ ereport(ERROR,
+ (errcode(ERRCODE_WRONG_OBJECT_TYPE),
+ errmsg("cannot lock rows in materialized 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))));
+ /* Okay only if the FDW supports it */
+ fdwroutine = GetFdwRoutineForRelation(rel, false);
+ if (fdwroutine->RefetchForeignRow == NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("cannot lock rows in foreign table \"%s\"",
+ RelationGetRelationName(rel))));
break;
default:
ereport(ERROR,
resultRelInfo->ri_TrigWhenExprs = NULL;
resultRelInfo->ri_TrigInstrument = NULL;
}
+ if (resultRelationDesc->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
+ resultRelInfo->ri_FdwRoutine = GetFdwRoutineForRelation(resultRelationDesc, true);
+ else
+ resultRelInfo->ri_FdwRoutine = NULL;
+ resultRelInfo->ri_FdwState = NULL;
resultRelInfo->ri_ConstraintExprs = NULL;
resultRelInfo->ri_junkFilter = NULL;
resultRelInfo->ri_projectReturning = NULL;
* if so it doesn't matter which one we pick.) However, it is sometimes
* necessary to fire triggers on other relations; this happens mainly when an
* RI update trigger queues additional triggers on other relations, which will
- * be processed in the context of the outer query. For efficiency's sake,
+ * be processed in the context of the outer query. For efficiency's sake,
* we want to have a ResultRelInfo for those triggers too; that can avoid
* repeated re-opening of the relation. (It also provides a way for EXPLAIN
* ANALYZE to report the runtimes of such triggers.) So we make additional
/*
* 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. Also, we need not
+ * 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);
/*
* ExecContextForcesOids
*
- * This is pretty grotty: when doing INSERT, UPDATE, or SELECT INTO,
+ * This is pretty grotty: when doing INSERT, UPDATE, or CREATE TABLE AS,
* we need to ensure that result tuples have space for an OID iff they are
* going to be stored into a relation that has OIDs. In other contexts
* we are free to choose whether to leave space for OIDs in result tuples
* the ModifyTable node, so ModifyTable has to set es_result_relation_info
* while initializing each subplan.
*
- * SELECT INTO is even uglier, because we don't have the INTO relation's
- * descriptor available when this code runs; we have to look aside at a
- * flag set by InitPlan().
+ * CREATE TABLE AS is even uglier, because we don't have the target relation's
+ * descriptor available when this code runs; we have to look aside at the
+ * flags passed to ExecutorStart().
*/
bool
ExecContextForcesOids(PlanState *planstate, bool *hasoids)
}
}
- if (planstate->state->es_select_into)
+ if (planstate->state->es_top_eflags & EXEC_FLAG_WITH_OIDS)
+ {
+ *hasoids = true;
+ return true;
+ }
+ if (planstate->state->es_top_eflags & EXEC_FLAG_WITHOUT_OIDS)
{
- *hasoids = planstate->state->es_into_oids;
+ *hasoids = false;
return true;
}
/*
* 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
+ * query did not fetch all rows from them. (We do this to ensure that
* such nodes have predictable results.)
*/
foreach(lc, estate->es_auxmodifytables)
}
/*
- * close any relations selected FOR UPDATE/FOR SHARE, again keeping locks
+ * close any relations selected FOR [KEY] UPDATE/SHARE, again keeping
+ * locks
*/
foreach(l, estate->es_rowMarks)
{
/* ----------------------------------------------------------------
* ExecutePlan
*
- * Processes the query plan until we have processed 'numberTuples' tuples,
+ * Processes the query plan until we have retrieved 'numberTuples' tuples,
* moving in the specified direction.
*
* Runs to completion if numberTuples is 0
/*
* ExecRelCheck --- check that tuple meets constraints for result relation
+ *
+ * Returns NULL if OK, else name of failed check constraint
*/
static const char *
ExecRelCheck(ResultRelInfo *resultRelInfo,
qual = resultRelInfo->ri_ConstraintExprs[i];
/*
- * NOTE: SQL92 specifies that a NULL result from a constraint
- * expression is not to be treated as a failure. Therefore, tell
- * ExecQual to return TRUE for NULL.
+ * NOTE: SQL specifies that a NULL result from a constraint expression
+ * is not to be treated as a failure. Therefore, tell ExecQual to
+ * return TRUE for NULL.
*/
if (!ExecQual(qual, econtext, true))
return check[i].ccname;
TupleTableSlot *slot, EState *estate)
{
Relation rel = resultRelInfo->ri_RelationDesc;
- TupleConstr *constr = rel->rd_att->constr;
+ TupleDesc tupdesc = RelationGetDescr(rel);
+ TupleConstr *constr = tupdesc->constr;
+ Bitmapset *modifiedCols;
+ Bitmapset *insertedCols;
+ Bitmapset *updatedCols;
Assert(constr);
if (constr->has_not_null)
{
- int natts = rel->rd_att->natts;
+ int natts = tupdesc->natts;
int attrChk;
for (attrChk = 1; attrChk <= natts; attrChk++)
{
- if (rel->rd_att->attrs[attrChk - 1]->attnotnull &&
+ if (tupdesc->attrs[attrChk - 1]->attnotnull &&
slot_attisnull(slot, attrChk))
+ {
+ char *val_desc;
+
+ insertedCols = GetInsertedColumns(resultRelInfo, estate);
+ updatedCols = GetUpdatedColumns(resultRelInfo, estate);
+ modifiedCols = bms_union(insertedCols, updatedCols);
+ val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel),
+ slot,
+ tupdesc,
+ modifiedCols,
+ 64);
+
ereport(ERROR,
(errcode(ERRCODE_NOT_NULL_VIOLATION),
errmsg("null value in column \"%s\" violates not-null constraint",
- NameStr(rel->rd_att->attrs[attrChk - 1]->attname)),
- errdetail("Failing row contains %s.",
- ExecBuildSlotValueDescription(slot, 64))));
+ NameStr(tupdesc->attrs[attrChk - 1]->attname)),
+ val_desc ? errdetail("Failing row contains %s.", val_desc) : 0,
+ errtablecol(rel, attrChk)));
+ }
}
}
const char *failed;
if ((failed = ExecRelCheck(resultRelInfo, slot, estate)) != NULL)
+ {
+ char *val_desc;
+
+ insertedCols = GetInsertedColumns(resultRelInfo, estate);
+ updatedCols = GetUpdatedColumns(resultRelInfo, estate);
+ modifiedCols = bms_union(insertedCols, updatedCols);
+ val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel),
+ slot,
+ tupdesc,
+ modifiedCols,
+ 64);
ereport(ERROR,
(errcode(ERRCODE_CHECK_VIOLATION),
errmsg("new row for relation \"%s\" violates check constraint \"%s\"",
RelationGetRelationName(rel), failed),
- errdetail("Failing row contains %s.",
- ExecBuildSlotValueDescription(slot, 64))));
+ val_desc ? errdetail("Failing row contains %s.", val_desc) : 0,
+ errtableconstraint(rel, failed)));
+ }
+ }
+}
+
+/*
+ * ExecWithCheckOptions -- check that tuple satisfies any WITH CHECK OPTIONs
+ * of the specified kind.
+ *
+ * Note that this needs to be called multiple times to ensure that all kinds of
+ * WITH CHECK OPTIONs are handled (both those from views which have the WITH
+ * CHECK OPTION set and from row level security policies). See ExecInsert()
+ * and ExecUpdate().
+ */
+void
+ExecWithCheckOptions(WCOKind kind, ResultRelInfo *resultRelInfo,
+ TupleTableSlot *slot, EState *estate)
+{
+ Relation rel = resultRelInfo->ri_RelationDesc;
+ TupleDesc tupdesc = RelationGetDescr(rel);
+ ExprContext *econtext;
+ ListCell *l1,
+ *l2;
+
+ /*
+ * We will use the EState's per-tuple context for evaluating constraint
+ * expressions (creating it if it's not already there).
+ */
+ econtext = GetPerTupleExprContext(estate);
+
+ /* Arrange for econtext's scan tuple to be the tuple under test */
+ econtext->ecxt_scantuple = slot;
+
+ /* Check each of the constraints */
+ forboth(l1, resultRelInfo->ri_WithCheckOptions,
+ l2, resultRelInfo->ri_WithCheckOptionExprs)
+ {
+ WithCheckOption *wco = (WithCheckOption *) lfirst(l1);
+ ExprState *wcoExpr = (ExprState *) lfirst(l2);
+
+ /*
+ * Skip any WCOs which are not the kind we are looking for at this
+ * time.
+ */
+ if (wco->kind != kind)
+ continue;
+
+ /*
+ * WITH CHECK OPTION checks are intended to ensure that the new tuple
+ * is visible (in the case of a view) or that it passes the
+ * 'with-check' policy (in the case of row security). If the qual
+ * evaluates to NULL or FALSE, then the new tuple won't be included in
+ * the view or doesn't pass the 'with-check' policy for the table. We
+ * need ExecQual to return FALSE for NULL to handle the view case (the
+ * opposite of what we do above for CHECK constraints).
+ */
+ if (!ExecQual((List *) wcoExpr, econtext, false))
+ {
+ char *val_desc;
+ Bitmapset *modifiedCols;
+ Bitmapset *insertedCols;
+ Bitmapset *updatedCols;
+
+ switch (wco->kind)
+ {
+ /*
+ * For WITH CHECK OPTIONs coming from views, we might be
+ * able to provide the details on the row, depending on
+ * the permissions on the relation (that is, if the user
+ * could view it directly anyway). For RLS violations, we
+ * don't include the data since we don't know if the user
+ * should be able to view the tuple as as that depends on
+ * the USING policy.
+ */
+ case WCO_VIEW_CHECK:
+ insertedCols = GetInsertedColumns(resultRelInfo, estate);
+ updatedCols = GetUpdatedColumns(resultRelInfo, estate);
+ modifiedCols = bms_union(insertedCols, updatedCols);
+ val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel),
+ slot,
+ tupdesc,
+ modifiedCols,
+ 64);
+
+ ereport(ERROR,
+ (errcode(ERRCODE_WITH_CHECK_OPTION_VIOLATION),
+ errmsg("new row violates WITH CHECK OPTION for \"%s\"",
+ wco->relname),
+ val_desc ? errdetail("Failing row contains %s.",
+ val_desc) : 0));
+ break;
+ case WCO_RLS_INSERT_CHECK:
+ case WCO_RLS_UPDATE_CHECK:
+ if (wco->polname != NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+ errmsg("new row violates row level security policy \"%s\" for \"%s\"",
+ wco->polname, wco->relname)));
+ else
+ ereport(ERROR,
+ (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+ errmsg("new row violates row level security policy for \"%s\"",
+ wco->relname)));
+ break;
+ case WCO_RLS_CONFLICT_CHECK:
+ if (wco->polname != NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+ errmsg("new row violates row level security policy \"%s\" (USING expression) for \"%s\"",
+ wco->polname, wco->relname)));
+ else
+ ereport(ERROR,
+ (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+ errmsg("new row violates row level security policy (USING expression) for \"%s\"",
+ wco->relname)));
+ break;
+ default:
+ elog(ERROR, "unrecognized WCO kind: %u", wco->kind);
+ break;
+ }
+ }
}
}
* ExecBuildSlotValueDescription -- construct a string representing a tuple
*
* This is intentionally very similar to BuildIndexValueDescription, but
- * unlike that function, we truncate long field values. That seems necessary
- * here since heap field values could be very long, whereas index entries
- * typically aren't so wide.
+ * unlike that function, we truncate long field values (to at most maxfieldlen
+ * bytes). That seems necessary here since heap field values could be very
+ * long, whereas index entries typically aren't so wide.
+ *
+ * Also, unlike the case with index entries, we need to be prepared to ignore
+ * dropped columns. We used to use the slot's tuple descriptor to decode the
+ * data, but the slot's descriptor doesn't identify dropped columns, so we
+ * now need to be passed the relation's descriptor.
+ *
+ * Note that, like BuildIndexValueDescription, if the user does not have
+ * permission to view any of the columns involved, a NULL is returned. Unlike
+ * BuildIndexValueDescription, if the user has access to view a subset of the
+ * column involved, that subset will be returned with a key identifying which
+ * columns they are.
*/
static char *
-ExecBuildSlotValueDescription(TupleTableSlot *slot, int maxfieldlen)
+ExecBuildSlotValueDescription(Oid reloid,
+ TupleTableSlot *slot,
+ TupleDesc tupdesc,
+ Bitmapset *modifiedCols,
+ int maxfieldlen)
{
StringInfoData buf;
- TupleDesc tupdesc = slot->tts_tupleDescriptor;
+ StringInfoData collist;
+ bool write_comma = false;
+ bool write_comma_collist = false;
int i;
+ AclResult aclresult;
+ bool table_perm = false;
+ bool any_perm = false;
- /* Make sure the tuple is fully deconstructed */
- slot_getallattrs(slot);
+ /*
+ * Check if RLS is enabled and should be active for the relation; if so,
+ * then don't return anything. Otherwise, go through normal permission
+ * checks.
+ */
+ if (check_enable_rls(reloid, InvalidOid, true) == RLS_ENABLED)
+ return NULL;
initStringInfo(&buf);
appendStringInfoChar(&buf, '(');
+ /*
+ * Check if the user has permissions to see the row. Table-level SELECT
+ * allows access to all columns. If the user does not have table-level
+ * SELECT then we check each column and include those the user has SELECT
+ * rights on. Additionally, we always include columns the user provided
+ * data for.
+ */
+ aclresult = pg_class_aclcheck(reloid, GetUserId(), ACL_SELECT);
+ if (aclresult != ACLCHECK_OK)
+ {
+ /* Set up the buffer for the column list */
+ initStringInfo(&collist);
+ appendStringInfoChar(&collist, '(');
+ }
+ else
+ table_perm = any_perm = true;
+
+ /* Make sure the tuple is fully deconstructed */
+ slot_getallattrs(slot);
+
for (i = 0; i < tupdesc->natts; i++)
{
+ bool column_perm = false;
char *val;
int vallen;
- if (slot->tts_isnull[i])
- val = "null";
- else
+ /* ignore dropped columns */
+ if (tupdesc->attrs[i]->attisdropped)
+ continue;
+
+ if (!table_perm)
{
- Oid foutoid;
- bool typisvarlena;
+ /*
+ * No table-level SELECT, so need to make sure they either have
+ * SELECT rights on the column or that they have provided the data
+ * for the column. If not, omit this column from the error
+ * message.
+ */
+ aclresult = pg_attribute_aclcheck(reloid, tupdesc->attrs[i]->attnum,
+ GetUserId(), ACL_SELECT);
+ if (bms_is_member(tupdesc->attrs[i]->attnum - FirstLowInvalidHeapAttributeNumber,
+ modifiedCols) || aclresult == ACLCHECK_OK)
+ {
+ column_perm = any_perm = true;
- getTypeOutputInfo(tupdesc->attrs[i]->atttypid,
- &foutoid, &typisvarlena);
- val = OidOutputFunctionCall(foutoid, slot->tts_values[i]);
- }
+ if (write_comma_collist)
+ appendStringInfoString(&collist, ", ");
+ else
+ write_comma_collist = true;
- if (i > 0)
- appendStringInfoString(&buf, ", ");
+ appendStringInfoString(&collist, NameStr(tupdesc->attrs[i]->attname));
+ }
+ }
- /* truncate if needed */
- vallen = strlen(val);
- if (vallen <= maxfieldlen)
- appendStringInfoString(&buf, val);
- else
+ if (table_perm || column_perm)
{
- vallen = pg_mbcliplen(val, vallen, maxfieldlen);
- appendBinaryStringInfo(&buf, val, vallen);
- appendStringInfoString(&buf, "...");
+ if (slot->tts_isnull[i])
+ val = "null";
+ else
+ {
+ Oid foutoid;
+ bool typisvarlena;
+
+ getTypeOutputInfo(tupdesc->attrs[i]->atttypid,
+ &foutoid, &typisvarlena);
+ val = OidOutputFunctionCall(foutoid, slot->tts_values[i]);
+ }
+
+ if (write_comma)
+ appendStringInfoString(&buf, ", ");
+ else
+ write_comma = true;
+
+ /* truncate if needed */
+ vallen = strlen(val);
+ if (vallen <= maxfieldlen)
+ appendStringInfoString(&buf, val);
+ else
+ {
+ vallen = pg_mbcliplen(val, vallen, maxfieldlen);
+ appendBinaryStringInfo(&buf, val, vallen);
+ appendStringInfoString(&buf, "...");
+ }
}
}
+ /* If we end up with zero columns being returned, then return NULL. */
+ if (!any_perm)
+ return NULL;
+
appendStringInfoChar(&buf, ')');
+ if (!table_perm)
+ {
+ appendStringInfoString(&collist, ") = ");
+ appendStringInfoString(&collist, buf.data);
+
+ return collist.data;
+ }
+
return buf.data;
}
+/*
+ * ExecUpdateLockMode -- find the appropriate UPDATE tuple lock mode for a
+ * given ResultRelInfo
+ */
+LockTupleMode
+ExecUpdateLockMode(EState *estate, ResultRelInfo *relinfo)
+{
+ Bitmapset *keyCols;
+ Bitmapset *updatedCols;
+
+ /*
+ * Compute lock mode to use. If columns that are part of the key have not
+ * been modified, then we can use a weaker lock, allowing for better
+ * concurrency.
+ */
+ updatedCols = GetUpdatedColumns(relinfo, estate);
+ keyCols = RelationGetIndexAttrBitmap(relinfo->ri_RelationDesc,
+ INDEX_ATTR_BITMAP_KEY);
+
+ if (bms_overlap(keyCols, updatedCols))
+ return LockTupleExclusive;
+
+ return LockTupleNoKeyExclusive;
+}
+
/*
* ExecFindRowMark -- find the ExecRowMark struct for given rangetable index
+ *
+ * If no such struct, either return NULL or throw error depending on missing_ok
*/
ExecRowMark *
-ExecFindRowMark(EState *estate, Index rti)
+ExecFindRowMark(EState *estate, Index rti, bool missing_ok)
{
ListCell *lc;
if (erm->rti == rti)
return erm;
}
- elog(ERROR, "failed to find ExecRowMark for rangetable index %u", rti);
- return NULL; /* keep compiler quiet */
+ if (!missing_ok)
+ elog(ERROR, "failed to find ExecRowMark for rangetable index %u", rti);
+ return NULL;
}
/*
aerm->rowmark = erm;
/* Look up the resjunk columns associated with this rowmark */
- if (erm->relation)
+ if (erm->markType != ROW_MARK_COPY)
{
- Assert(erm->markType != ROW_MARK_COPY);
-
- /* if child rel, need tableoid */
- if (erm->rti != erm->prti)
- {
- snprintf(resname, sizeof(resname), "tableoid%u", erm->rowmarkId);
- aerm->toidAttNo = ExecFindJunkAttributeInTlist(targetlist,
- resname);
- if (!AttributeNumberIsValid(aerm->toidAttNo))
- elog(ERROR, "could not find junk %s column", resname);
- }
-
- /* always need ctid for real relations */
+ /* need ctid for all methods other than COPY */
snprintf(resname, sizeof(resname), "ctid%u", erm->rowmarkId);
aerm->ctidAttNo = ExecFindJunkAttributeInTlist(targetlist,
resname);
}
else
{
- Assert(erm->markType == ROW_MARK_COPY);
-
+ /* need wholerow if COPY */
snprintf(resname, sizeof(resname), "wholerow%u", erm->rowmarkId);
aerm->wholeAttNo = ExecFindJunkAttributeInTlist(targetlist,
resname);
elog(ERROR, "could not find junk %s column", resname);
}
+ /* if child rel, need tableoid */
+ if (erm->rti != erm->prti)
+ {
+ snprintf(resname, sizeof(resname), "tableoid%u", erm->rowmarkId);
+ aerm->toidAttNo = ExecFindJunkAttributeInTlist(targetlist,
+ resname);
+ if (!AttributeNumberIsValid(aerm->toidAttNo))
+ elog(ERROR, "could not find junk %s column", resname);
+ }
+
return aerm;
}
* epqstate - state for EvalPlanQual rechecking
* relation - table containing tuple
* rti - rangetable index of table containing tuple
+ * lockmode - requested tuple lock mode
* *tid - t_ctid from the outdated tuple (ie, next updated version)
* priorXmax - t_xmax from the outdated tuple
*
*
* Returns a slot containing the new candidate update/delete tuple, or
* NULL if we determine we shouldn't process the row.
+ *
+ * Note: properly, lockmode should be declared as enum LockTupleMode,
+ * but we use "int" to avoid having to include heapam.h in executor.h.
*/
TupleTableSlot *
EvalPlanQual(EState *estate, EPQState *epqstate,
- Relation relation, Index rti,
+ Relation relation, Index rti, int lockmode,
ItemPointer tid, TransactionId priorXmax)
{
TupleTableSlot *slot;
/*
* Get and lock the updated version of the row; if fail, return NULL.
*/
- copyTuple = EvalPlanQualFetch(estate, relation, LockTupleExclusive,
+ copyTuple = EvalPlanQualFetch(estate, relation, lockmode, LockWaitBlock,
tid, priorXmax);
if (copyTuple == NULL)
*tid = copyTuple->t_self;
/*
- * Need to run a recheck subquery. Initialize or reinitialize EPQ state.
+ * Need to run a recheck subquery. Initialize or reinitialize EPQ state.
*/
EvalPlanQualBegin(epqstate, estate);
* estate - executor state data
* relation - table containing tuple
* lockmode - requested tuple lock mode
+ * wait_policy - requested lock wait policy
* *tid - t_ctid from the outdated tuple (ie, next updated version)
* priorXmax - t_xmax from the outdated tuple
*
* Returns a palloc'd copy of the newest tuple version, or NULL if we find
* that there is no newest version (ie, the row was deleted not updated).
+ * We also return NULL if the tuple is locked and the wait policy is to skip
+ * such tuples.
+ *
* If successful, we have locked the newest tuple version, so caller does not
* need to worry about it changing anymore.
*
*/
HeapTuple
EvalPlanQualFetch(EState *estate, Relation relation, int lockmode,
+ LockWaitPolicy wait_policy,
ItemPointer tid, TransactionId priorXmax)
{
HeapTuple copyTuple = NULL;
if (heap_fetch(relation, &SnapshotDirty, &tuple, &buffer, true, NULL))
{
HTSU_Result test;
- ItemPointerData update_ctid;
- TransactionId update_xmax;
+ HeapUpdateFailureData hufd;
/*
* If xmin isn't what we're expecting, the slot must have been
- * recycled and reused for an unrelated tuple. This implies that
+ * recycled and reused for an unrelated tuple. This implies that
* the latest version of the row was deleted, so we need do
* nothing. (Should be safe to examine xmin without getting
- * buffer's content lock, since xmin never changes in an existing
- * tuple.)
+ * buffer's content lock. We assume reading a TransactionId to be
+ * atomic, and Xmin never changes in an existing tuple, except to
+ * invalid or frozen, and neither of those can match priorXmax.)
*/
if (!TransactionIdEquals(HeapTupleHeaderGetXmin(tuple.t_data),
priorXmax))
/*
* If tuple is being updated by other transaction then we have to
- * wait for its commit/abort.
+ * wait for its commit/abort, or die trying.
*/
if (TransactionIdIsValid(SnapshotDirty.xmax))
{
ReleaseBuffer(buffer);
- XactLockTableWait(SnapshotDirty.xmax);
+ switch (wait_policy)
+ {
+ case LockWaitBlock:
+ XactLockTableWait(SnapshotDirty.xmax,
+ relation, &tuple.t_self,
+ XLTW_FetchUpdated);
+ break;
+ case LockWaitSkip:
+ if (!ConditionalXactLockTableWait(SnapshotDirty.xmax))
+ return NULL; /* skip instead of waiting */
+ break;
+ case LockWaitError:
+ if (!ConditionalXactLockTableWait(SnapshotDirty.xmax))
+ ereport(ERROR,
+ (errcode(ERRCODE_LOCK_NOT_AVAILABLE),
+ errmsg("could not obtain lock on row in relation \"%s\"",
+ RelationGetRelationName(relation))));
+ break;
+ }
continue; /* loop back to repeat heap_fetch */
}
/*
* If tuple was inserted by our own transaction, we have to check
* cmin against es_output_cid: cmin >= current CID means our
- * command cannot see the tuple, so we should ignore it. Without
- * this we are open to the "Halloween problem" of indefinitely
- * re-updating the same tuple. (We need not check cmax because
- * HeapTupleSatisfiesDirty will consider a tuple deleted by our
- * transaction dead, regardless of cmax.) We just checked that
- * priorXmax == xmin, so we can test that variable instead of
+ * command cannot see the tuple, so we should ignore it. Otherwise
+ * heap_lock_tuple() will throw an error, and so would any later
+ * attempt to update or delete the tuple. (We need not check cmax
+ * because HeapTupleSatisfiesDirty will consider a tuple deleted
+ * by our transaction dead, regardless of cmax.) We just checked
+ * that priorXmax == xmin, so we can test that variable instead of
* doing HeapTupleHeaderGetXmin again.
*/
if (TransactionIdIsCurrentTransactionId(priorXmax) &&
/*
* This is a live tuple, so now try to lock it.
*/
- test = heap_lock_tuple(relation, &tuple, &buffer,
- &update_ctid, &update_xmax,
+ test = heap_lock_tuple(relation, &tuple,
estate->es_output_cid,
- lockmode, false);
+ lockmode, wait_policy,
+ false, &buffer, &hufd);
/* We now have two pins on the buffer, get rid of one */
ReleaseBuffer(buffer);
switch (test)
{
case HeapTupleSelfUpdated:
- /* treat it as deleted; do not process */
+
+ /*
+ * The target tuple was already updated or deleted by the
+ * current command, or by a later command in the current
+ * transaction. We *must* ignore the tuple in the former
+ * case, so as to avoid the "Halloween problem" of
+ * repeated update attempts. In the latter case it might
+ * be sensible to fetch the updated tuple instead, but
+ * doing so would require changing heap_update and
+ * heap_delete to not complain about updating "invisible"
+ * tuples, which seems pretty scary (heap_lock_tuple will
+ * not complain, but few callers expect
+ * HeapTupleInvisible, and we're not one of them). So for
+ * now, treat the tuple as deleted and do not process.
+ */
ReleaseBuffer(buffer);
return NULL;
ereport(ERROR,
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
errmsg("could not serialize access due to concurrent update")));
- if (!ItemPointerEquals(&update_ctid, &tuple.t_self))
+
+ /* Should not encounter speculative tuple on recheck */
+ Assert(!HeapTupleHeaderIsSpeculative(tuple.t_data));
+ if (!ItemPointerEquals(&hufd.ctid, &tuple.t_self))
{
/* it was updated, so look at the updated version */
- tuple.t_self = update_ctid;
+ tuple.t_self = hufd.ctid;
/* updated row should have xmin matching this xmax */
- priorXmax = update_xmax;
+ priorXmax = hufd.xmax;
continue;
}
/* tuple was deleted, so give up */
return NULL;
+ case HeapTupleWouldBlock:
+ ReleaseBuffer(buffer);
+ return NULL;
+
+ case HeapTupleInvisible:
+ elog(ERROR, "attempted to lock invisible tuple");
+
default:
ReleaseBuffer(buffer);
elog(ERROR, "unrecognized heap_lock_tuple status: %u",
/* updated, so look at the updated row */
tuple.t_self = tuple.t_data->t_ctid;
/* updated row should have xmin matching this xmax */
- priorXmax = HeapTupleHeaderGetXmax(tuple.t_data);
+ priorXmax = HeapTupleHeaderGetUpdateXid(tuple.t_data);
ReleaseBuffer(buffer);
/* loop back to fetch next in chain */
}
/*
* EvalPlanQualSetPlan -- set or change subplan of an EPQState.
*
- * We need this so that ModifyTuple can deal with multiple subplans.
+ * We need this so that ModifyTable can deal with multiple subplans.
*/
void
EvalPlanQualSetPlan(EPQState *epqstate, Plan *subplan, List *auxrowmarks)
/*
* Fetch the current row values for any non-locked relations that need
- * to be scanned by an EvalPlanQual operation. origslot must have been set
+ * to be scanned by an EvalPlanQual operation. origslot must have been set
* to contain the current result row (top-level row) that we need to recheck.
*/
void
/* clear any leftover test tuple for this rel */
EvalPlanQualSetTuple(epqstate, erm->rti, NULL);
- if (erm->relation)
+ /* if child rel, must check whether it produced this row */
+ if (erm->rti != erm->prti)
{
- Buffer buffer;
+ Oid tableoid;
- Assert(erm->markType == ROW_MARK_REFERENCE);
+ datum = ExecGetJunkAttribute(epqstate->origslot,
+ aerm->toidAttNo,
+ &isNull);
+ /* non-locked rels could be on the inside of outer joins */
+ if (isNull)
+ continue;
+ tableoid = DatumGetObjectId(datum);
- /* if child rel, must check whether it produced this row */
- if (erm->rti != erm->prti)
+ Assert(OidIsValid(erm->relid));
+ if (tableoid != erm->relid)
{
- Oid tableoid;
+ /* this child is inactive right now */
+ continue;
+ }
+ }
- datum = ExecGetJunkAttribute(epqstate->origslot,
- aerm->toidAttNo,
- &isNull);
- /* non-locked rels could be on the inside of outer joins */
- if (isNull)
- continue;
- tableoid = DatumGetObjectId(datum);
+ if (erm->markType == ROW_MARK_REFERENCE)
+ {
+ HeapTuple copyTuple;
- if (tableoid != RelationGetRelid(erm->relation))
- {
- /* this child is inactive right now */
- continue;
- }
- }
+ Assert(erm->relation != NULL);
/* fetch the tuple's ctid */
datum = ExecGetJunkAttribute(epqstate->origslot,
/* non-locked rels could be on the inside of outer joins */
if (isNull)
continue;
- tuple.t_self = *((ItemPointer) DatumGetPointer(datum));
- /* okay, fetch the tuple */
- if (!heap_fetch(erm->relation, SnapshotAny, &tuple, &buffer,
- false, NULL))
- elog(ERROR, "failed to fetch tuple for EvalPlanQual recheck");
+ /* fetch requests on foreign tables must be passed to their FDW */
+ if (erm->relation->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
+ {
+ FdwRoutine *fdwroutine;
+ bool updated = false;
+
+ fdwroutine = GetFdwRoutineForRelation(erm->relation, false);
+ /* this should have been checked already, but let's be safe */
+ if (fdwroutine->RefetchForeignRow == NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("cannot lock rows in foreign table \"%s\"",
+ RelationGetRelationName(erm->relation))));
+ copyTuple = fdwroutine->RefetchForeignRow(epqstate->estate,
+ erm,
+ datum,
+ &updated);
+ if (copyTuple == NULL)
+ elog(ERROR, "failed to fetch tuple for EvalPlanQual recheck");
+
+ /*
+ * Ideally we'd insist on updated == false here, but that
+ * assumes that FDWs can track that exactly, which they might
+ * not be able to. So just ignore the flag.
+ */
+ }
+ else
+ {
+ /* ordinary table, fetch the tuple */
+ Buffer buffer;
- /* successful, copy and store tuple */
- EvalPlanQualSetTuple(epqstate, erm->rti,
- heap_copytuple(&tuple));
- ReleaseBuffer(buffer);
+ tuple.t_self = *((ItemPointer) DatumGetPointer(datum));
+ if (!heap_fetch(erm->relation, SnapshotAny, &tuple, &buffer,
+ false, NULL))
+ elog(ERROR, "failed to fetch tuple for EvalPlanQual recheck");
+
+ /* successful, copy tuple */
+ copyTuple = heap_copytuple(&tuple);
+ ReleaseBuffer(buffer);
+ }
+
+ /* store tuple */
+ EvalPlanQualSetTuple(epqstate, erm->rti, copyTuple);
}
else
{
/* build a temporary HeapTuple control structure */
tuple.t_len = HeapTupleHeaderGetDatumLength(td);
- ItemPointerSetInvalid(&(tuple.t_self));
- tuple.t_tableOid = InvalidOid;
tuple.t_data = td;
+ /* relation might be a foreign table, if so provide tableoid */
+ tuple.t_tableOid = erm->relid;
+ /* also copy t_ctid in case there's valid data there */
+ tuple.t_self = td->t_ctid;
/* copy and store tuple */
EvalPlanQualSetTuple(epqstate, erm->rti,
* the snapshot, rangetable, result-rel info, and external Param info.
* They need their own copies of local state, including a tuple table,
* es_param_exec_vals, etc.
+ *
+ * The ResultRelInfo array management is trickier than it looks. We
+ * create a fresh array for the child but copy all the content from the
+ * parent. This is because it's okay for the child to share any
+ * per-relation state the parent has already created --- but if the child
+ * sets up any ResultRelInfo fields, such as its own junkfilter, that
+ * state must *not* propagate back to the parent. (For one thing, the
+ * pointed-to data is in a memory context that won't last long enough.)
*/
estate->es_direction = ForwardScanDirection;
estate->es_snapshot = parentestate->es_snapshot;
estate->es_plannedstmt = parentestate->es_plannedstmt;
estate->es_junkFilter = parentestate->es_junkFilter;
estate->es_output_cid = parentestate->es_output_cid;
- estate->es_result_relations = parentestate->es_result_relations;
- estate->es_num_result_relations = parentestate->es_num_result_relations;
- estate->es_result_relation_info = parentestate->es_result_relation_info;
+ if (parentestate->es_num_result_relations > 0)
+ {
+ int numResultRelations = parentestate->es_num_result_relations;
+ ResultRelInfo *resultRelInfos;
+
+ resultRelInfos = (ResultRelInfo *)
+ palloc(numResultRelations * sizeof(ResultRelInfo));
+ memcpy(resultRelInfos, parentestate->es_result_relations,
+ numResultRelations * sizeof(ResultRelInfo));
+ estate->es_result_relations = resultRelInfos;
+ estate->es_num_result_relations = numResultRelations;
+ }
+ /* es_result_relation_info must NOT be copied */
/* 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 */
/*
/*
* Each EState must have its own es_epqScanDone state, but if we have
- * nested EPQ checks they should share es_epqTuple arrays. This allows
+ * nested EPQ checks they should share es_epqTuple arrays. This allows
* sub-rechecks to inherit the values being examined by an outer recheck.
*/
estate->es_epqScanDone = (bool *) palloc0(rtsize * sizeof(bool));
* 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. (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.)
+ * all.
*/
Assert(estate->es_subplanstates == NIL);
foreach(l, parentestate->es_plannedstmt->subplans)
Plan *subplan = (Plan *) lfirst(l);
PlanState *subplanstate;
- /* Don't initialize ModifyTable subplans, per comment above */
- if (IsA(subplan, ModifyTable))
- subplanstate = NULL;
- else
- subplanstate = ExecInitNode(subplan, estate, 0);
-
+ subplanstate = ExecInitNode(subplan, estate, 0);
estate->es_subplanstates = lappend(estate->es_subplanstates,
subplanstate);
}
*
* This is a cut-down version of ExecutorEnd(); basically we want to do most
* of the normal cleanup, but *not* close result relations (which we are
- * just sharing from the outer query). We do, however, have to close any
+ * just sharing from the outer query). We do, however, have to close any
* trigger target relations that got opened, since those are not shared.
* (There probably shouldn't be any of the latter, but just in case...)
*/
epqstate->planstate = NULL;
epqstate->origslot = NULL;
}
-
-
-/*
- * Support for SELECT INTO (a/k/a CREATE TABLE AS)
- *
- * We implement SELECT INTO by diverting SELECT's normal output with
- * a specialized DestReceiver type.
- */
-
-typedef struct
-{
- DestReceiver pub; /* publicly-known function pointers */
- EState *estate; /* EState we are working with */
- Relation rel; /* Relation to write to */
- int hi_options; /* heap_insert performance options */
- BulkInsertState bistate; /* bulk insert state */
-} DR_intorel;
-
-/*
- * OpenIntoRel --- actually create the SELECT INTO target relation
- *
- * This also replaces QueryDesc->dest with the special DestReceiver for
- * SELECT INTO. We assume that the correct result tuple type has already
- * been placed in queryDesc->tupDesc.
- */
-static void
-OpenIntoRel(QueryDesc *queryDesc)
-{
- IntoClause *into = queryDesc->plannedstmt->intoClause;
- EState *estate = queryDesc->estate;
- TupleDesc intoTupDesc = queryDesc->tupDesc;
- Relation intoRelationDesc;
- char *intoName;
- Oid namespaceId;
- Oid tablespaceId;
- Datum reloptions;
- Oid intoRelationId;
- DR_intorel *myState;
- RangeTblEntry *rte;
- AttrNumber attnum;
- static char *validnsps[] = HEAP_RELOPT_NAMESPACES;
-
- Assert(into);
-
- /*
- * XXX This code needs to be kept in sync with DefineRelation(). Maybe we
- * should try to use that function instead.
- */
-
- /*
- * Check consistency of arguments
- */
- if (into->onCommit != ONCOMMIT_NOOP
- && into->rel->relpersistence != RELPERSISTENCE_TEMP)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
- errmsg("ON COMMIT can only be used on temporary tables")));
-
- {
- AclResult aclresult;
- int i;
-
- for (i = 0; i < intoTupDesc->natts; i++)
- {
- Oid atttypid = intoTupDesc->attrs[i]->atttypid;
-
- aclresult = pg_type_aclcheck(atttypid, GetUserId(), ACL_USAGE);
- if (aclresult != ACLCHECK_OK)
- aclcheck_error(aclresult, ACL_KIND_TYPE,
- format_type_be(atttypid));
- }
- }
-
- /*
- * If a column name list was specified in CREATE TABLE AS, override the
- * column names derived from the query. (Too few column names are OK, too
- * many are not.) It would probably be all right to scribble directly on
- * the query's result tupdesc, but let's be safe and make a copy.
- */
- if (into->colNames)
- {
- ListCell *lc;
-
- intoTupDesc = CreateTupleDescCopy(intoTupDesc);
- attnum = 1;
- foreach(lc, into->colNames)
- {
- char *colname = strVal(lfirst(lc));
-
- if (attnum > intoTupDesc->natts)
- ereport(ERROR,
- (errcode(ERRCODE_SYNTAX_ERROR),
- errmsg("CREATE TABLE AS specifies too many column names")));
- namestrcpy(&(intoTupDesc->attrs[attnum - 1]->attname), colname);
- attnum++;
- }
- }
-
- /*
- * 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.
- */
- if (into->rel->relpersistence == RELPERSISTENCE_TEMP
- && InSecurityRestrictedOperation())
- ereport(ERROR,
- (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
- errmsg("cannot create temporary table within security-restricted operation")));
-
- /*
- * Select tablespace to use. If not specified, use default tablespace
- * (which may in turn default to database's default).
- */
- if (into->tableSpaceName)
- {
- tablespaceId = get_tablespace_oid(into->tableSpaceName, false);
- }
- else
- {
- tablespaceId = GetDefaultTablespace(into->rel->relpersistence);
- /* note InvalidOid is OK in this case */
- }
-
- /* Check permissions except when using the database's default space */
- if (OidIsValid(tablespaceId) && tablespaceId != MyDatabaseTableSpace)
- {
- AclResult aclresult;
-
- aclresult = pg_tablespace_aclcheck(tablespaceId, GetUserId(),
- ACL_CREATE);
-
- if (aclresult != ACLCHECK_OK)
- aclcheck_error(aclresult, ACL_KIND_TABLESPACE,
- get_tablespace_name(tablespaceId));
- }
-
- /* Parse and validate any reloptions */
- reloptions = transformRelOptions((Datum) 0,
- into->options,
- NULL,
- validnsps,
- true,
- false);
- (void) heap_reloptions(RELKIND_RELATION, reloptions, true);
-
- /* Now we can actually create the new relation */
- intoRelationId = heap_create_with_catalog(intoName,
- namespaceId,
- tablespaceId,
- InvalidOid,
- InvalidOid,
- InvalidOid,
- GetUserId(),
- intoTupDesc,
- NIL,
- RELKIND_RELATION,
- into->rel->relpersistence,
- false,
- false,
- true,
- 0,
- into->onCommit,
- reloptions,
- true,
- allowSystemTableMods);
- Assert(intoRelationId != InvalidOid);
-
- /*
- * Advance command counter so that the newly-created relation's catalog
- * tuples will be visible to heap_open.
- */
- CommandCounterIncrement();
-
- /*
- * If necessary, create a TOAST table for the INTO relation. Note that
- * AlterTableCreateToastTable ends with CommandCounterIncrement(), so that
- * the TOAST table will be visible for insertion.
- */
- reloptions = transformRelOptions((Datum) 0,
- into->options,
- "toast",
- validnsps,
- true,
- false);
-
- (void) heap_reloptions(RELKIND_TOASTVALUE, reloptions, true);
-
- AlterTableCreateToastTable(intoRelationId, reloptions);
-
- /*
- * And open the constructed table for writing.
- */
- intoRelationDesc = heap_open(intoRelationId, AccessExclusiveLock);
-
- /*
- * Check INSERT permission on the constructed table.
- */
- rte = makeNode(RangeTblEntry);
- rte->rtekind = RTE_RELATION;
- rte->relid = intoRelationId;
- rte->relkind = RELKIND_RELATION;
- rte->requiredPerms = ACL_INSERT;
-
- for (attnum = 1; attnum <= intoTupDesc->natts; attnum++)
- rte->modifiedCols = bms_add_member(rte->modifiedCols,
- attnum - FirstLowInvalidHeapAttributeNumber);
-
- ExecCheckRTPerms(list_make1(rte), true);
-
- /*
- * Now replace the query's DestReceiver with one for SELECT INTO
- */
- queryDesc->dest = CreateDestReceiver(DestIntoRel);
- myState = (DR_intorel *) queryDesc->dest;
- Assert(myState->pub.mydest == DestIntoRel);
- myState->estate = estate;
- myState->rel = intoRelationDesc;
-
- /*
- * We can skip WAL-logging the insertions, unless PITR or streaming
- * replication is in use. We can skip the FSM in any case.
- */
- myState->hi_options = HEAP_INSERT_SKIP_FSM |
- (XLogIsNeeded() ? 0 : HEAP_INSERT_SKIP_WAL);
- myState->bistate = GetBulkInsertState();
-
- /* Not using WAL requires smgr_targblock be initially invalid */
- Assert(RelationGetTargetBlock(intoRelationDesc) == InvalidBlockNumber);
-}
-
-/*
- * CloseIntoRel --- clean up SELECT INTO at ExecutorEnd time
- */
-static void
-CloseIntoRel(QueryDesc *queryDesc)
-{
- DR_intorel *myState = (DR_intorel *) queryDesc->dest;
-
- /* OpenIntoRel might never have gotten called */
- if (myState && myState->pub.mydest == DestIntoRel && myState->rel)
- {
- FreeBulkInsertState(myState->bistate);
-
- /* If we skipped using WAL, must heap_sync before commit */
- if (myState->hi_options & HEAP_INSERT_SKIP_WAL)
- heap_sync(myState->rel);
-
- /* close rel, but keep lock until commit */
- heap_close(myState->rel, NoLock);
-
- myState->rel = NULL;
- }
-}
-
-/*
- * CreateIntoRelDestReceiver -- create a suitable DestReceiver object
- */
-DestReceiver *
-CreateIntoRelDestReceiver(void)
-{
- DR_intorel *self = (DR_intorel *) palloc0(sizeof(DR_intorel));
-
- self->pub.receiveSlot = intorel_receive;
- self->pub.rStartup = intorel_startup;
- self->pub.rShutdown = intorel_shutdown;
- self->pub.rDestroy = intorel_destroy;
- self->pub.mydest = DestIntoRel;
-
- /* private fields will be set by OpenIntoRel */
-
- return (DestReceiver *) self;
-}
-
-/*
- * intorel_startup --- executor startup
- */
-static void
-intorel_startup(DestReceiver *self, int operation, TupleDesc typeinfo)
-{
- /* no-op */
-}
-
-/*
- * intorel_receive --- receive one tuple
- */
-static void
-intorel_receive(TupleTableSlot *slot, DestReceiver *self)
-{
- DR_intorel *myState = (DR_intorel *) self;
- HeapTuple tuple;
-
- /*
- * get the heap tuple out of the tuple table slot, making sure we have a
- * writable copy
- */
- tuple = ExecMaterializeSlot(slot);
-
- /*
- * force assignment of new OID (see comments in ExecInsert)
- */
- if (myState->rel->rd_rel->relhasoids)
- HeapTupleSetOid(tuple, InvalidOid);
-
- heap_insert(myState->rel,
- tuple,
- myState->estate->es_output_cid,
- myState->hi_options,
- myState->bistate);
-
- /* We know this is a newly created relation, so there are no indexes */
-}
-
-/*
- * intorel_shutdown --- executor end
- */
-static void
-intorel_shutdown(DestReceiver *self)
-{
- /* no-op */
-}
-
-/*
- * intorel_destroy --- release DestReceiver object
- */
-static void
-intorel_destroy(DestReceiver *self)
-{
- pfree(self);
-}
projects / postgresql / blobdiff