/* ----------------------------------------------------------------
* ExecBitmapHeapReScan(node)
* ----------------------------------------------------------------
*/
void
ExecBitmapHeapReScan(BitmapHeapScanState *node, ExprContext *exprCtxt)
{
EState *estate;
Index scanrelid;
estate = node->ss.ps.state;
scanrelid = ((BitmapHeapScan *) node->ss.ps.plan)->scan.scanrelid;
/*
* If we are being passed an outer tuple, link it into the "regular"
* per-tuple econtext for possible qual eval.
*/
if (exprCtxt != NULL)
{
ExprContext *stdecontext;
stdecontext = node->ss.ps.ps_ExprContext;
stdecontext->ecxt_outertuple = exprCtxt->ecxt_outertuple;
}
/* If this is re-scanning of PlanQual ... */
if (estate->es_evTuple != NULL &&
estate->es_evTuple[scanrelid - 1] != NULL)
{
estate->es_evTupleNull[scanrelid - 1] = false;
}
/* rescan to release any page pin */
heap_rescan(node->ss.ss_currentScanDesc, NULL);
/* undo bogus "seq scan" count (see notes in ExecInitBitmapHeapScan) */
pgstat_discount_heap_scan(&node->ss.ss_currentScanDesc->rs_pgstat_info);
if (node->tbm)
tbm_free(node->tbm);
node->tbm = NULL;
node->tbmres = NULL;
if (node->odbm)
odbm_free(node->odbm);
node->odbm = NULL;
/*
* Always rescan the input immediately, to ensure we can pass down any
* outer tuple that might be used in index quals.
*/
ExecReScan(outerPlanState(node), exprCtxt);
}
/* ----------------------------------------------------------------
* ExecInitBitmapHeapScan
*
* Initializes the scan's state information.
* ----------------------------------------------------------------
*/
BitmapHeapScanState *
ExecInitBitmapHeapScan(BitmapHeapScan *node, EState *estate, int eflags)
{
BitmapHeapScanState *scanstate;
Relation currentRelation;
/* check for unsupported flags */
Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK)));
/*
* Assert caller didn't ask for an unsafe snapshot --- see comments at
* head of file.
*/
Assert(IsMVCCSnapshot(estate->es_snapshot));
/*
* create state structure
*/
scanstate = makeNode(BitmapHeapScanState);
scanstate->ss.ps.plan = (Plan *) node;
scanstate->ss.ps.state = estate;
scanstate->tbm = NULL;
scanstate->tbmres = NULL;
/*
* Miscellaneous initialization
*
* create expression context for node
*/
ExecAssignExprContext(estate, &scanstate->ss.ps);
scanstate->ss.ps.ps_TupFromTlist = false;
/*
* initialize child expressions
*/
scanstate->ss.ps.targetlist = (List *)
ExecInitExpr((Expr *) node->scan.plan.targetlist,
(PlanState *) scanstate);
scanstate->ss.ps.qual = (List *)
ExecInitExpr((Expr *) node->scan.plan.qual,
(PlanState *) scanstate);
scanstate->bitmapqualorig = (List *)
ExecInitExpr((Expr *) node->bitmapqualorig,
(PlanState *) scanstate);
#define BITMAPHEAPSCAN_NSLOTS 2
/*
* tuple table initialization
*/
ExecInitResultTupleSlot(estate, &scanstate->ss.ps);
ExecInitScanTupleSlot(estate, &scanstate->ss);
/*
* open the base relation and acquire appropriate lock on it.
*/
currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid);
scanstate->ss.ss_currentRelation = currentRelation;
/*
* Even though we aren't going to do a conventional seqscan, it is useful
* to create a HeapScanDesc --- this checks the relation size and sets up
* statistical infrastructure for us.
*/
scanstate->ss.ss_currentScanDesc = heap_beginscan(currentRelation,
estate->es_snapshot,
0,
NULL);
/*
* One problem is that heap_beginscan counts a "sequential scan" start,
* when we actually aren't doing any such thing. Reverse out the added
* scan count. (Eventually we may want to count bitmap scans separately.)
*/
pgstat_discount_heap_scan(&scanstate->ss.ss_currentScanDesc->rs_pgstat_info);
/*
* get the scan type from the relation descriptor.
*/
ExecAssignScanType(&scanstate->ss, RelationGetDescr(currentRelation));
/*
* Initialize result tuple type and projection info.
*/
ExecAssignResultTypeFromTL(&scanstate->ss.ps);
ExecAssignScanProjectionInfo(&scanstate->ss);
/*
* initialize child nodes
*
* We do this last because the child nodes will open indexscans on our
* relation's indexes, and we want to be sure we have acquired a lock on
* the relation first.
*/
outerPlanState(scanstate) = ExecInitNode(outerPlan(node), estate, eflags);
/*
* all done.
*/
return scanstate;
}
/* ----------------------------------------------------------------
* ExecInitBitmapHeapScan
*
* Initializes the scan's state information.
* ----------------------------------------------------------------
*/
BitmapHeapScanState *
ExecInitBitmapHeapScan(BitmapHeapScan *node, EState *estate, int eflags)
{
BitmapHeapScanState *scanstate;
RangeTblEntry *rtentry;
Index relid;
Oid reloid;
Relation currentRelation;
/* check for unsupported flags */
Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK)));
/*
* create state structure
*/
scanstate = makeNode(BitmapHeapScanState);
scanstate->ss.ps.plan = (Plan *) node;
scanstate->ss.ps.state = estate;
scanstate->tbm = NULL;
scanstate->tbmres = NULL;
/*
* Miscellaneous initialization
*
* create expression context for node
*/
ExecAssignExprContext(estate, &scanstate->ss.ps);
/*
* initialize child expressions
*/
scanstate->ss.ps.targetlist = (List *)
ExecInitExpr((Expr *) node->scan.plan.targetlist,
(PlanState *) scanstate);
scanstate->ss.ps.qual = (List *)
ExecInitExpr((Expr *) node->scan.plan.qual,
(PlanState *) scanstate);
scanstate->bitmapqualorig = (List *)
ExecInitExpr((Expr *) node->bitmapqualorig,
(PlanState *) scanstate);
#define BITMAPHEAPSCAN_NSLOTS 2
/*
* tuple table initialization
*/
ExecInitResultTupleSlot(estate, &scanstate->ss.ps);
ExecInitScanTupleSlot(estate, &scanstate->ss);
CXT1_printf("ExecInitBitmapHeapScan: context is %d\n", CurrentMemoryContext);
/*
* open the base relation and acquire AccessShareLock on it.
*/
relid = node->scan.scanrelid;
rtentry = rt_fetch(relid, estate->es_range_table);
reloid = rtentry->relid;
currentRelation = heap_open(reloid, AccessShareLock);
scanstate->ss.ss_currentRelation = currentRelation;
/*
* Even though we aren't going to do a conventional seqscan, it is useful
* to create a HeapScanDesc --- this checks the relation size and sets up
* statistical infrastructure for us.
*/
scanstate->ss.ss_currentScanDesc = heap_beginscan(currentRelation,
estate->es_snapshot,
0,
NULL);
/*
* One problem is that heap_beginscan counts a "sequential scan" start,
* when we actually aren't doing any such thing. Reverse out the added
* scan count. (Eventually we may want to count bitmap scans separately.)
*/
pgstat_discount_heap_scan(&scanstate->ss.ss_currentScanDesc->rs_pgstat_info);
/*
* get the scan type from the relation descriptor.
*/
ExecAssignScanType(&scanstate->ss, RelationGetDescr(currentRelation), false);
/*
* Initialize result tuple type and projection info.
*/
ExecAssignResultTypeFromTL(&scanstate->ss.ps);
ExecAssignScanProjectionInfo(&scanstate->ss);
/*
* initialize child nodes
*
* We do this last because the child nodes will open indexscans on our
* relation's indexes, and we want to be sure we have acquired a lock
* on the relation first.
*/
outerPlanState(scanstate) = ExecInitNode(outerPlan(node), estate, eflags);
if (IsA(outerPlan(node), BitmapIndexScan))
node->inmem =
(((BitmapIndexScan*)outerPlan(node))->indexam !=
BITMAP_AM_OID);
else if (IsA(outerPlan(node), BitmapAnd))
node->inmem = ((BitmapAnd*)outerPlan(node))->inmem;
else if (IsA(outerPlan(node), BitmapOr))
node->inmem = ((BitmapOr*)outerPlan(node))->inmem;
else
node->inmem = true;
/*
* all done.
*/
return scanstate;
}
