mirror of
https://git.postgresql.org/git/postgresql.git
synced 2024-12-09 08:10:09 +08:00
EvalPlanQual was thoroughly broken for concurrent update/delete on inheritance
trees (mostly my fault). Repair. Also fix long-standing bug in ExecReplace: after recomputing a concurrently updated tuple, we must recheck constraints. Make EvalPlanQual leak memory with somewhat less enthusiasm than before, although plugging leaks fully will require more changes than I care to risk in a dot-release.
This commit is contained in:
Tom Lane
parent
e611348894
commit
a4155d3bbd
@ -27,7 +27,7 @@
|
||||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $Header: /cvsroot/pgsql/src/backend/executor/execMain.c,v 1.139 2001/03/22 03:59:26 momjian Exp $
|
||||
* $Header: /cvsroot/pgsql/src/backend/executor/execMain.c,v 1.140 2001/05/15 00:33:36 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -603,11 +603,17 @@ InitPlan(CmdType operation, Query *parseTree, Plan *plan, EState *estate)
|
||||
*/
|
||||
{
|
||||
int nSlots = ExecCountSlotsNode(plan);
|
||||
TupleTable tupleTable = ExecCreateTupleTable(nSlots + 10); /* why add ten? - jolly */
|
||||
|
||||
estate->es_tupleTable = tupleTable;
|
||||
estate->es_tupleTable = ExecCreateTupleTable(nSlots + 10); /* why add ten? - jolly */
|
||||
}
|
||||
|
||||
/* mark EvalPlanQual not active */
|
||||
estate->es_origPlan = plan;
|
||||
estate->es_evalPlanQual = NULL;
|
||||
estate->es_evTuple = NULL;
|
||||
estate->es_evTupleNull = NULL;
|
||||
estate->es_useEvalPlan = false;
|
||||
|
||||
/*
|
||||
* initialize the private state information for all the nodes in the
|
||||
* query tree. This opens files, allocates storage and leaves us
|
||||
@ -774,11 +780,6 @@ InitPlan(CmdType operation, Query *parseTree, Plan *plan, EState *estate)
|
||||
|
||||
estate->es_into_relation_descriptor = intoRelationDesc;
|
||||
|
||||
estate->es_origPlan = plan;
|
||||
estate->es_evalPlanQual = NULL;
|
||||
estate->es_evTuple = NULL;
|
||||
estate->es_useEvalPlan = false;
|
||||
|
||||
return tupType;
|
||||
}
|
||||
|
||||
@ -1038,13 +1039,10 @@ lnext: ;
|
||||
elog(ERROR, "ExecutePlan: NO (junk) `%s' was found!",
|
||||
erm->resname);
|
||||
|
||||
/*
|
||||
* Unlike the UPDATE/DELETE case, a null result is
|
||||
* possible here, when the referenced table is on the
|
||||
* nullable side of an outer join. Ignore nulls.
|
||||
*/
|
||||
/* shouldn't ever get a null result... */
|
||||
if (isNull)
|
||||
continue;
|
||||
elog(ERROR, "ExecutePlan: (junk) `%s' is NULL!",
|
||||
erm->resname);
|
||||
|
||||
tuple.t_self = *((ItemPointer) DatumGetPointer(datum));
|
||||
test = heap_mark4update(erm->relation, &tuple, &buffer);
|
||||
@ -1072,7 +1070,7 @@ lnext: ;
|
||||
|
||||
/*
|
||||
* if tuple was deleted or PlanQual failed for
|
||||
* updated tuple - we have not return this
|
||||
* updated tuple - we must not return this
|
||||
* tuple!
|
||||
*/
|
||||
goto lnext;
|
||||
@ -1340,6 +1338,7 @@ ldelete:;
|
||||
goto ldelete;
|
||||
}
|
||||
}
|
||||
/* tuple already deleted; nothing to do */
|
||||
return;
|
||||
|
||||
default:
|
||||
@ -1434,14 +1433,20 @@ ExecReplace(TupleTableSlot *slot,
|
||||
|
||||
/*
|
||||
* Check the constraints of the tuple
|
||||
*
|
||||
* If we generate a new candidate tuple after EvalPlanQual testing,
|
||||
* we must loop back here and recheck constraints. (We don't need to
|
||||
* redo triggers, however. If there are any BEFORE triggers then
|
||||
* trigger.c will have done mark4update to lock the correct tuple,
|
||||
* so there's no need to do them again.)
|
||||
*/
|
||||
lreplace:;
|
||||
if (resultRelationDesc->rd_att->constr)
|
||||
ExecConstraints("ExecReplace", resultRelInfo, slot, estate);
|
||||
|
||||
/*
|
||||
* replace the heap tuple
|
||||
*/
|
||||
lreplace:;
|
||||
result = heap_update(resultRelationDesc, tupleid, tuple, &ctid);
|
||||
switch (result)
|
||||
{
|
||||
@ -1467,6 +1472,7 @@ lreplace:;
|
||||
goto lreplace;
|
||||
}
|
||||
}
|
||||
/* tuple already deleted; nothing to do */
|
||||
return;
|
||||
|
||||
default:
|
||||
@ -1595,21 +1601,122 @@ ExecConstraints(char *caller, ResultRelInfo *resultRelInfo,
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Check a modified tuple to see if we want to process its updated version
|
||||
* under READ COMMITTED rules.
|
||||
*
|
||||
* See backend/executor/README for some info about how this works.
|
||||
*/
|
||||
TupleTableSlot *
|
||||
EvalPlanQual(EState *estate, Index rti, ItemPointer tid)
|
||||
{
|
||||
evalPlanQual *epq = (evalPlanQual *) estate->es_evalPlanQual;
|
||||
evalPlanQual *oldepq;
|
||||
EState *epqstate = NULL;
|
||||
evalPlanQual *epq;
|
||||
EState *epqstate;
|
||||
Relation relation;
|
||||
Buffer buffer;
|
||||
HeapTupleData tuple;
|
||||
bool endNode = true;
|
||||
HeapTuple copyTuple = NULL;
|
||||
int rtsize;
|
||||
bool endNode;
|
||||
|
||||
Assert(rti != 0);
|
||||
|
||||
/*
|
||||
* find relation containing target tuple
|
||||
*/
|
||||
if (estate->es_result_relation_info != NULL &&
|
||||
estate->es_result_relation_info->ri_RangeTableIndex == rti)
|
||||
{
|
||||
relation = estate->es_result_relation_info->ri_RelationDesc;
|
||||
}
|
||||
else
|
||||
{
|
||||
List *l;
|
||||
|
||||
relation = NULL;
|
||||
foreach(l, estate->es_rowMark)
|
||||
{
|
||||
if (((execRowMark *) lfirst(l))->rti == rti)
|
||||
{
|
||||
relation = ((execRowMark *) lfirst(l))->relation;
|
||||
break;
|
||||
}
|
||||
}
|
||||
if (relation == NULL)
|
||||
elog(ERROR, "EvalPlanQual: can't find RTE %d", (int) rti);
|
||||
}
|
||||
|
||||
/*
|
||||
* fetch tid tuple
|
||||
*
|
||||
* Loop here to deal with updated or busy tuples
|
||||
*/
|
||||
tuple.t_self = *tid;
|
||||
for (;;)
|
||||
{
|
||||
Buffer buffer;
|
||||
|
||||
heap_fetch(relation, SnapshotDirty, &tuple, &buffer);
|
||||
if (tuple.t_data != NULL)
|
||||
{
|
||||
TransactionId xwait = SnapshotDirty->xmax;
|
||||
|
||||
if (TransactionIdIsValid(SnapshotDirty->xmin))
|
||||
elog(ERROR, "EvalPlanQual: t_xmin is uncommitted ?!");
|
||||
|
||||
/*
|
||||
* If tuple is being updated by other transaction then we have
|
||||
* to wait for its commit/abort.
|
||||
*/
|
||||
if (TransactionIdIsValid(xwait))
|
||||
{
|
||||
ReleaseBuffer(buffer);
|
||||
XactLockTableWait(xwait);
|
||||
continue;
|
||||
}
|
||||
|
||||
/*
|
||||
* We got tuple - now copy it for use by recheck query.
|
||||
*/
|
||||
copyTuple = heap_copytuple(&tuple);
|
||||
ReleaseBuffer(buffer);
|
||||
break;
|
||||
}
|
||||
|
||||
/*
|
||||
* Oops! Invalid tuple. Have to check is it updated or deleted.
|
||||
* Note that it's possible to get invalid SnapshotDirty->tid if
|
||||
* tuple updated by this transaction. Have we to check this ?
|
||||
*/
|
||||
if (ItemPointerIsValid(&(SnapshotDirty->tid)) &&
|
||||
!(ItemPointerEquals(&(tuple.t_self), &(SnapshotDirty->tid))))
|
||||
{
|
||||
/* updated, so look at the updated copy */
|
||||
tuple.t_self = SnapshotDirty->tid;
|
||||
continue;
|
||||
}
|
||||
|
||||
/*
|
||||
* Deleted or updated by this transaction; forget it.
|
||||
*/
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/*
|
||||
* For UPDATE/DELETE we have to return tid of actual row we're
|
||||
* executing PQ for.
|
||||
*/
|
||||
*tid = tuple.t_self;
|
||||
|
||||
/*
|
||||
* Need to run a recheck subquery. Find or create a PQ stack entry.
|
||||
*/
|
||||
epq = (evalPlanQual *) estate->es_evalPlanQual;
|
||||
rtsize = length(estate->es_range_table);
|
||||
endNode = true;
|
||||
|
||||
if (epq != NULL && epq->rti == 0)
|
||||
{
|
||||
/* Top PQ stack entry is idle, so re-use it */
|
||||
Assert(!(estate->es_useEvalPlan) &&
|
||||
epq->estate.es_evalPlanQual == NULL);
|
||||
epq->rti = rti;
|
||||
@ -1627,20 +1734,23 @@ EvalPlanQual(EState *estate, Index rti, ItemPointer tid)
|
||||
{
|
||||
do
|
||||
{
|
||||
evalPlanQual *oldepq;
|
||||
|
||||
/* pop previous PlanQual from the stack */
|
||||
epqstate = &(epq->estate);
|
||||
oldepq = (evalPlanQual *) epqstate->es_evalPlanQual;
|
||||
Assert(oldepq->rti != 0);
|
||||
/* stop execution */
|
||||
ExecEndNode(epq->plan, epq->plan);
|
||||
epqstate->es_tupleTable->next = 0;
|
||||
ExecDropTupleTable(epqstate->es_tupleTable, true);
|
||||
epqstate->es_tupleTable = NULL;
|
||||
heap_freetuple(epqstate->es_evTuple[epq->rti - 1]);
|
||||
epqstate->es_evTuple[epq->rti - 1] = NULL;
|
||||
/* push current PQ to freePQ stack */
|
||||
oldepq->free = epq;
|
||||
epq = oldepq;
|
||||
estate->es_evalPlanQual = (Pointer) epq;
|
||||
} while (epq->rti != rti);
|
||||
estate->es_evalPlanQual = (Pointer) epq;
|
||||
}
|
||||
|
||||
/*
|
||||
@ -1655,37 +1765,55 @@ EvalPlanQual(EState *estate, Index rti, ItemPointer tid)
|
||||
if (newepq == NULL) /* first call or freePQ stack is empty */
|
||||
{
|
||||
newepq = (evalPlanQual *) palloc(sizeof(evalPlanQual));
|
||||
/* Init EState */
|
||||
newepq->free = NULL;
|
||||
/*
|
||||
* Each stack level has its own copy of the plan tree. This
|
||||
* is wasteful, but necessary as long as plan nodes point to
|
||||
* exec state nodes rather than vice versa. Note that copyfuncs.c
|
||||
* doesn't attempt to copy the exec state nodes, which is a good
|
||||
* thing in this situation.
|
||||
*/
|
||||
newepq->plan = copyObject(estate->es_origPlan);
|
||||
/*
|
||||
* Init stack level's EState. We share top level's copy of
|
||||
* es_result_relations array and other non-changing status.
|
||||
* We need our own tupletable, es_param_exec_vals, and other
|
||||
* changeable state.
|
||||
*/
|
||||
epqstate = &(newepq->estate);
|
||||
memset(epqstate, 0, sizeof(EState));
|
||||
epqstate->type = T_EState;
|
||||
memcpy(epqstate, estate, sizeof(EState));
|
||||
epqstate->es_direction = ForwardScanDirection;
|
||||
epqstate->es_snapshot = estate->es_snapshot;
|
||||
epqstate->es_range_table = estate->es_range_table;
|
||||
epqstate->es_param_list_info = estate->es_param_list_info;
|
||||
if (estate->es_origPlan->nParamExec > 0)
|
||||
epqstate->es_param_exec_vals = (ParamExecData *)
|
||||
palloc(estate->es_origPlan->nParamExec *
|
||||
sizeof(ParamExecData));
|
||||
epqstate->es_tupleTable =
|
||||
ExecCreateTupleTable(estate->es_tupleTable->size);
|
||||
/* ... rest */
|
||||
newepq->plan = copyObject(estate->es_origPlan);
|
||||
newepq->free = NULL;
|
||||
epqstate->es_evTupleNull = (bool *)
|
||||
palloc(length(estate->es_range_table) * sizeof(bool));
|
||||
if (epq == NULL) /* first call */
|
||||
epqstate->es_tupleTable = NULL;
|
||||
epqstate->es_per_tuple_exprcontext = NULL;
|
||||
/*
|
||||
* Each epqstate must have its own es_evTupleNull state,
|
||||
* but all the stack entries share es_evTuple state. This
|
||||
* allows sub-rechecks to inherit the value being examined by
|
||||
* an outer recheck.
|
||||
*/
|
||||
epqstate->es_evTupleNull = (bool *) palloc(rtsize * sizeof(bool));
|
||||
if (epq == NULL)
|
||||
{
|
||||
/* first PQ stack entry */
|
||||
epqstate->es_evTuple = (HeapTuple *)
|
||||
palloc(length(estate->es_range_table) * sizeof(HeapTuple));
|
||||
memset(epqstate->es_evTuple, 0,
|
||||
length(estate->es_range_table) * sizeof(HeapTuple));
|
||||
palloc(rtsize * sizeof(HeapTuple));
|
||||
memset(epqstate->es_evTuple, 0, rtsize * sizeof(HeapTuple));
|
||||
}
|
||||
else
|
||||
{
|
||||
/* later stack entries share the same storage */
|
||||
epqstate->es_evTuple = epq->estate.es_evTuple;
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
/* recycle previously used EState */
|
||||
epqstate = &(newepq->estate);
|
||||
}
|
||||
/* push current PQ to the stack */
|
||||
epqstate->es_evalPlanQual = (Pointer) epq;
|
||||
epq = newepq;
|
||||
@ -1694,123 +1822,49 @@ EvalPlanQual(EState *estate, Index rti, ItemPointer tid)
|
||||
endNode = false;
|
||||
}
|
||||
|
||||
Assert(epq->rti == rti);
|
||||
epqstate = &(epq->estate);
|
||||
|
||||
/*
|
||||
* Ok - we're requested for the same RTE (-:)). I'm not sure about
|
||||
* ability to use ExecReScan instead of ExecInitNode, so...
|
||||
* Ok - we're requested for the same RTE. Unfortunately we still
|
||||
* have to end and restart execution of the plan, because ExecReScan
|
||||
* wouldn't ensure that upper plan nodes would reset themselves. We
|
||||
* could make that work if insertion of the target tuple were integrated
|
||||
* with the Param mechanism somehow, so that the upper plan nodes know
|
||||
* that their children's outputs have changed.
|
||||
*/
|
||||
if (endNode)
|
||||
{
|
||||
/* stop execution */
|
||||
ExecEndNode(epq->plan, epq->plan);
|
||||
epqstate->es_tupleTable->next = 0;
|
||||
ExecDropTupleTable(epqstate->es_tupleTable, true);
|
||||
epqstate->es_tupleTable = NULL;
|
||||
}
|
||||
|
||||
/* free old RTE' tuple */
|
||||
if (epqstate->es_evTuple[epq->rti - 1] != NULL)
|
||||
{
|
||||
heap_freetuple(epqstate->es_evTuple[epq->rti - 1]);
|
||||
epqstate->es_evTuple[epq->rti - 1] = NULL;
|
||||
}
|
||||
|
||||
/* ** fetch tid tuple ** */
|
||||
if (estate->es_result_relation_info != NULL &&
|
||||
estate->es_result_relation_info->ri_RangeTableIndex == rti)
|
||||
relation = estate->es_result_relation_info->ri_RelationDesc;
|
||||
else
|
||||
{
|
||||
List *l;
|
||||
|
||||
foreach(l, estate->es_rowMark)
|
||||
{
|
||||
if (((execRowMark *) lfirst(l))->rti == rti)
|
||||
break;
|
||||
}
|
||||
relation = ((execRowMark *) lfirst(l))->relation;
|
||||
}
|
||||
tuple.t_self = *tid;
|
||||
for (;;)
|
||||
{
|
||||
heap_fetch(relation, SnapshotDirty, &tuple, &buffer);
|
||||
if (tuple.t_data != NULL)
|
||||
{
|
||||
TransactionId xwait = SnapshotDirty->xmax;
|
||||
|
||||
if (TransactionIdIsValid(SnapshotDirty->xmin))
|
||||
{
|
||||
elog(NOTICE, "EvalPlanQual: t_xmin is uncommitted ?!");
|
||||
Assert(!TransactionIdIsValid(SnapshotDirty->xmin));
|
||||
elog(ERROR, "Aborting this transaction");
|
||||
}
|
||||
|
||||
/*
|
||||
* If tuple is being updated by other transaction then we have
|
||||
* to wait for its commit/abort.
|
||||
*/
|
||||
if (TransactionIdIsValid(xwait))
|
||||
{
|
||||
ReleaseBuffer(buffer);
|
||||
XactLockTableWait(xwait);
|
||||
continue;
|
||||
}
|
||||
|
||||
/*
|
||||
* Nice! We got tuple - now copy it.
|
||||
*/
|
||||
if (epqstate->es_evTuple[epq->rti - 1] != NULL)
|
||||
heap_freetuple(epqstate->es_evTuple[epq->rti - 1]);
|
||||
epqstate->es_evTuple[epq->rti - 1] = heap_copytuple(&tuple);
|
||||
ReleaseBuffer(buffer);
|
||||
break;
|
||||
}
|
||||
|
||||
/*
|
||||
* Ops! Invalid tuple. Have to check is it updated or deleted.
|
||||
* Note that it's possible to get invalid SnapshotDirty->tid if
|
||||
* tuple updated by this transaction. Have we to check this ?
|
||||
*/
|
||||
if (ItemPointerIsValid(&(SnapshotDirty->tid)) &&
|
||||
!(ItemPointerEquals(&(tuple.t_self), &(SnapshotDirty->tid))))
|
||||
{
|
||||
tuple.t_self = SnapshotDirty->tid; /* updated ... */
|
||||
continue;
|
||||
}
|
||||
|
||||
/*
|
||||
* Deleted or updated by this transaction. Do not (re-)start
|
||||
* execution of this PQ. Continue previous PQ.
|
||||
*/
|
||||
oldepq = (evalPlanQual *) epqstate->es_evalPlanQual;
|
||||
if (oldepq != NULL)
|
||||
{
|
||||
Assert(oldepq->rti != 0);
|
||||
/* push current PQ to freePQ stack */
|
||||
oldepq->free = epq;
|
||||
epq = oldepq;
|
||||
epqstate = &(epq->estate);
|
||||
estate->es_evalPlanQual = (Pointer) epq;
|
||||
}
|
||||
else
|
||||
{
|
||||
epq->rti = 0; /* this is the first (oldest) */
|
||||
estate->es_useEvalPlan = false; /* PQ - mark as free and */
|
||||
return (NULL); /* continue Query execution */
|
||||
}
|
||||
}
|
||||
/*
|
||||
* free old RTE' tuple, if any, and store target tuple where relation's
|
||||
* scan node will see it
|
||||
*/
|
||||
if (epqstate->es_evTuple[rti - 1] != NULL)
|
||||
heap_freetuple(epqstate->es_evTuple[rti - 1]);
|
||||
epqstate->es_evTuple[rti - 1] = copyTuple;
|
||||
|
||||
/*
|
||||
* Initialize for new recheck query; be careful to copy down state
|
||||
* that might have changed in top EState.
|
||||
*/
|
||||
epqstate->es_result_relation_info = estate->es_result_relation_info;
|
||||
epqstate->es_junkFilter = estate->es_junkFilter;
|
||||
if (estate->es_origPlan->nParamExec > 0)
|
||||
memset(epqstate->es_param_exec_vals, 0,
|
||||
estate->es_origPlan->nParamExec * sizeof(ParamExecData));
|
||||
memset(epqstate->es_evTupleNull, false,
|
||||
length(estate->es_range_table) * sizeof(bool));
|
||||
Assert(epqstate->es_tupleTable->next == 0);
|
||||
ExecInitNode(epq->plan, epqstate, NULL);
|
||||
memset(epqstate->es_evTupleNull, false, rtsize * sizeof(bool));
|
||||
epqstate->es_useEvalPlan = false;
|
||||
Assert(epqstate->es_tupleTable == NULL);
|
||||
epqstate->es_tupleTable =
|
||||
ExecCreateTupleTable(estate->es_tupleTable->size);
|
||||
|
||||
/*
|
||||
* For UPDATE/DELETE we have to return tid of actual row we're
|
||||
* executing PQ for.
|
||||
*/
|
||||
*tid = tuple.t_self;
|
||||
ExecInitNode(epq->plan, epqstate, NULL);
|
||||
|
||||
return EvalPlanQualNext(estate);
|
||||
}
|
||||
@ -1833,8 +1887,10 @@ lpqnext:;
|
||||
*/
|
||||
if (TupIsNull(slot))
|
||||
{
|
||||
/* stop execution */
|
||||
ExecEndNode(epq->plan, epq->plan);
|
||||
epqstate->es_tupleTable->next = 0;
|
||||
ExecDropTupleTable(epqstate->es_tupleTable, true);
|
||||
epqstate->es_tupleTable = NULL;
|
||||
heap_freetuple(epqstate->es_evTuple[epq->rti - 1]);
|
||||
epqstate->es_evTuple[epq->rti - 1] = NULL;
|
||||
/* pop old PQ from the stack */
|
||||
@ -1872,8 +1928,10 @@ EndEvalPlanQual(EState *estate)
|
||||
|
||||
for (;;)
|
||||
{
|
||||
/* stop execution */
|
||||
ExecEndNode(epq->plan, epq->plan);
|
||||
epqstate->es_tupleTable->next = 0;
|
||||
ExecDropTupleTable(epqstate->es_tupleTable, true);
|
||||
epqstate->es_tupleTable = NULL;
|
||||
if (epqstate->es_evTuple[epq->rti - 1] != NULL)
|
||||
{
|
||||
heap_freetuple(epqstate->es_evTuple[epq->rti - 1]);
|
||||
|
||||
@ -8,7 +8,7 @@
|
||||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $Header: /cvsroot/pgsql/src/backend/executor/nodeAppend.c,v 1.41 2001/05/08 19:47:02 tgl Exp $
|
||||
* $Header: /cvsroot/pgsql/src/backend/executor/nodeAppend.c,v 1.42 2001/05/15 00:33:36 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -64,6 +64,7 @@
|
||||
|
||||
static bool exec_append_initialize_next(Append *node);
|
||||
|
||||
|
||||
/* ----------------------------------------------------------------
|
||||
* exec_append_initialize_next
|
||||
*
|
||||
@ -79,7 +80,6 @@ exec_append_initialize_next(Append *node)
|
||||
EState *estate;
|
||||
AppendState *appendstate;
|
||||
int whichplan;
|
||||
int nplans;
|
||||
|
||||
/*
|
||||
* get information from the append node
|
||||
@ -87,9 +87,8 @@ exec_append_initialize_next(Append *node)
|
||||
estate = node->plan.state;
|
||||
appendstate = node->appendstate;
|
||||
whichplan = appendstate->as_whichplan;
|
||||
nplans = appendstate->as_nplans;
|
||||
|
||||
if (whichplan < 0)
|
||||
if (whichplan < appendstate->as_firstplan)
|
||||
{
|
||||
|
||||
/*
|
||||
@ -98,17 +97,17 @@ exec_append_initialize_next(Append *node)
|
||||
* ExecProcAppend that we are at the end of the line by returning
|
||||
* FALSE
|
||||
*/
|
||||
appendstate->as_whichplan = 0;
|
||||
appendstate->as_whichplan = appendstate->as_firstplan;
|
||||
return FALSE;
|
||||
}
|
||||
else if (whichplan >= nplans)
|
||||
else if (whichplan > appendstate->as_lastplan)
|
||||
{
|
||||
|
||||
/*
|
||||
* as above, end the scan if we go beyond the last scan in our
|
||||
* list..
|
||||
*/
|
||||
appendstate->as_whichplan = nplans - 1;
|
||||
appendstate->as_whichplan = appendstate->as_lastplan;
|
||||
return FALSE;
|
||||
}
|
||||
else
|
||||
@ -145,7 +144,9 @@ exec_append_initialize_next(Append *node)
|
||||
* structures get allocated in the executor's top level memory
|
||||
* block instead of that of the call to ExecProcAppend.)
|
||||
*
|
||||
* Returns the scan result of the first scan.
|
||||
* Special case: during an EvalPlanQual recheck query of an inherited
|
||||
* target relation, we only want to initialize and scan the single
|
||||
* subplan that corresponds to the target relation being checked.
|
||||
* ----------------------------------------------------------------
|
||||
*/
|
||||
bool
|
||||
@ -175,12 +176,32 @@ ExecInitAppend(Append *node, EState *estate, Plan *parent)
|
||||
* create new AppendState for our append node
|
||||
*/
|
||||
appendstate = makeNode(AppendState);
|
||||
appendstate->as_whichplan = 0;
|
||||
appendstate->as_nplans = nplans;
|
||||
appendstate->as_initialized = initialized;
|
||||
|
||||
node->appendstate = appendstate;
|
||||
|
||||
/*
|
||||
* Do we want to scan just one subplan? (Special case for EvalPlanQual)
|
||||
* XXX pretty dirty way of determining that this case applies ...
|
||||
*/
|
||||
if (node->isTarget && estate->es_evTuple != NULL)
|
||||
{
|
||||
int tplan;
|
||||
|
||||
tplan = estate->es_result_relation_info - estate->es_result_relations;
|
||||
Assert(tplan >= 0 && tplan < nplans);
|
||||
|
||||
appendstate->as_firstplan = tplan;
|
||||
appendstate->as_lastplan = tplan;
|
||||
}
|
||||
else
|
||||
{
|
||||
/* normal case, scan all subplans */
|
||||
appendstate->as_firstplan = 0;
|
||||
appendstate->as_lastplan = nplans - 1;
|
||||
}
|
||||
|
||||
/*
|
||||
* Miscellaneous initialization
|
||||
*
|
||||
@ -197,10 +218,10 @@ ExecInitAppend(Append *node, EState *estate, Plan *parent)
|
||||
ExecInitResultTupleSlot(estate, &appendstate->cstate);
|
||||
|
||||
/*
|
||||
* call ExecInitNode on each of the plans in our list and save the
|
||||
* call ExecInitNode on each of the plans to be executed and save the
|
||||
* results into the array "initialized"
|
||||
*/
|
||||
for (i = 0; i < nplans; i++)
|
||||
for (i = appendstate->as_firstplan; i <= appendstate->as_lastplan; i++)
|
||||
{
|
||||
appendstate->as_whichplan = i;
|
||||
exec_append_initialize_next(node);
|
||||
@ -218,7 +239,7 @@ ExecInitAppend(Append *node, EState *estate, Plan *parent)
|
||||
/*
|
||||
* return the result from the first subplan's initialization
|
||||
*/
|
||||
appendstate->as_whichplan = 0;
|
||||
appendstate->as_whichplan = appendstate->as_firstplan;
|
||||
exec_append_initialize_next(node);
|
||||
|
||||
return TRUE;
|
||||
@ -357,10 +378,9 @@ void
|
||||
ExecReScanAppend(Append *node, ExprContext *exprCtxt, Plan *parent)
|
||||
{
|
||||
AppendState *appendstate = node->appendstate;
|
||||
int nplans = length(node->appendplans);
|
||||
int i;
|
||||
|
||||
for (i = 0; i < nplans; i++)
|
||||
for (i = appendstate->as_firstplan; i <= appendstate->as_lastplan; i++)
|
||||
{
|
||||
Plan *subnode;
|
||||
|
||||
@ -383,6 +403,6 @@ ExecReScanAppend(Append *node, ExprContext *exprCtxt, Plan *parent)
|
||||
ExecReScan(subnode, exprCtxt, (Plan *) node);
|
||||
}
|
||||
}
|
||||
appendstate->as_whichplan = 0;
|
||||
appendstate->as_whichplan = appendstate->as_firstplan;
|
||||
exec_append_initialize_next(node);
|
||||
}
|
||||
|
||||
@ -7,7 +7,7 @@
|
||||
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $Id: execnodes.h,v 1.58 2001/05/07 00:43:25 tgl Exp $
|
||||
* $Id: execnodes.h,v 1.59 2001/05/15 00:33:36 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -353,6 +353,8 @@ typedef struct ResultState
|
||||
* AppendState information
|
||||
*
|
||||
* whichplan which plan is being executed (0 .. n-1)
|
||||
* firstplan first plan to execute (usually 0)
|
||||
* lastplan last plan to execute (usually n-1)
|
||||
* nplans how many plans are in the list
|
||||
* initialized array of ExecInitNode() results
|
||||
* ----------------
|
||||
@ -361,6 +363,8 @@ typedef struct AppendState
|
||||
{
|
||||
CommonState cstate; /* its first field is NodeTag */
|
||||
int as_whichplan;
|
||||
int as_firstplan;
|
||||
int as_lastplan;
|
||||
int as_nplans;
|
||||
bool *as_initialized;
|
||||
} AppendState;
|
||||
|
||||
Loading…
Reference in New Issue
Block a user