/* ----------------------------------------------------------------
* ExecInitBitmapIndexScan
*
* Initializes the index scan's state information.
* ----------------------------------------------------------------
*/
BitmapIndexScanState *
ExecInitBitmapIndexScan(BitmapIndexScan *node, EState *estate, int eflags)
{
BitmapIndexScanState *indexstate;
bool relistarget;
/* check for unsupported flags */
Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK)));
/*
* create state structure
*/
indexstate = makeNode(BitmapIndexScanState);
indexstate->ss.ps.plan = (Plan *) node;
indexstate->ss.ps.state = estate;
/* normally we don't make the result bitmap till runtime */
indexstate->biss_result = NULL;
/*
* Miscellaneous initialization
*
* We do not need a standard exprcontext for this node, though we may
* decide below to create a runtime-key exprcontext
*/
/*
* initialize child expressions
*
* We don't need to initialize targetlist or qual since neither are used.
*
* Note: we don't initialize all of the indexqual expression, only the
* sub-parts corresponding to runtime keys (see below).
*/
#define BITMAPINDEXSCAN_NSLOTS 0
/*
* We do not open or lock the base relation here. We assume that an
* ancestor BitmapHeapScan node is holding AccessShareLock (or better) on
* the heap relation throughout the execution of the plan tree.
*/
indexstate->ss.ss_currentRelation = NULL;
indexstate->ss.ss_currentScanDesc = NULL;
/*
* If we are just doing EXPLAIN (ie, aren't going to run the plan), stop
* here. This allows an index-advisor plugin to EXPLAIN a plan containing
* references to nonexistent indexes.
*/
if (eflags & EXEC_FLAG_EXPLAIN_ONLY)
return indexstate;
/*
* Open the index relation.
*
* If the parent table is one of the target relations of the query, then
* InitPlan already opened and write-locked the index, so we can avoid
* taking another lock here. Otherwise we need a normal reader's lock.
*/
relistarget = ExecRelationIsTargetRelation(estate, node->scan.scanrelid);
indexstate->biss_RelationDesc = index_open(node->indexid,
relistarget ? NoLock : AccessShareLock);
/*
* Initialize index-specific scan state
*/
indexstate->biss_RuntimeKeysReady = false;
/*
* build the index scan keys from the index qualification
*/
ExecIndexBuildScanKeys((PlanState *) indexstate,
indexstate->biss_RelationDesc,
node->indexqual,
node->indexstrategy,
node->indexsubtype,
&indexstate->biss_ScanKeys,
&indexstate->biss_NumScanKeys,
&indexstate->biss_RuntimeKeys,
&indexstate->biss_NumRuntimeKeys,
&indexstate->biss_ArrayKeys,
&indexstate->biss_NumArrayKeys);
/*
* If we have runtime keys or array keys, we need an ExprContext to
* evaluate them. We could just create a "standard" plan node exprcontext,
* but to keep the code looking similar to nodeIndexscan.c, it seems
* better to stick with the approach of using a separate ExprContext.
*/
if (indexstate->biss_NumRuntimeKeys != 0 ||
indexstate->biss_NumArrayKeys != 0)
{
ExprContext *stdecontext = indexstate->ss.ps.ps_ExprContext;
ExecAssignExprContext(estate, &indexstate->ss.ps);
indexstate->biss_RuntimeContext = indexstate->ss.ps.ps_ExprContext;
indexstate->ss.ps.ps_ExprContext = stdecontext;
}
else
{
indexstate->biss_RuntimeContext = NULL;
}
/*
* Initialize scan descriptor.
*/
indexstate->biss_ScanDesc =
index_beginscan_multi(indexstate->biss_RelationDesc,
estate->es_snapshot,
indexstate->biss_NumScanKeys,
indexstate->biss_ScanKeys);
/*
* all done.
*/
return indexstate;
}
/* ----------------------------------------------------------------
* ExecInitBitmapIndexScan
*
* Initializes the index scan's state information.
* ----------------------------------------------------------------
*/
BitmapIndexScanState *
ExecInitBitmapIndexScan(BitmapIndexScan *node, EState *estate, int eflags)
{
BitmapIndexScanState *indexstate;
ScanKey scanKeys;
int numScanKeys;
ExprState **runtimeKeyInfo;
bool have_runtime_keys;
/* check for unsupported flags */
Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK)));
/*
* create state structure
*/
indexstate = makeNode(BitmapIndexScanState);
indexstate->ss.ps.plan = (Plan *) node;
indexstate->ss.ps.state = estate;
/* normally we don't make the result bitmap till runtime */
indexstate->biss_result = NULL;
indexstate->odbiss_result = NULL;
/*
* Miscellaneous initialization
*
* We do not need a standard exprcontext for this node, though we may
* decide below to create a runtime-key exprcontext
*/
/*
* initialize child expressions
*
* We don't need to initialize targetlist or qual since neither are used.
*
* Note: we don't initialize all of the indexqual expression, only the
* sub-parts corresponding to runtime keys (see below).
*/
#define BITMAPINDEXSCAN_NSLOTS 0
/*
* Initialize index-specific scan state
*/
indexstate->biss_RuntimeKeysReady = false;
CXT1_printf("ExecInitBitmapIndexScan: context is %d\n", CurrentMemoryContext);
/*
* build the index scan keys from the index qualification
*/
have_runtime_keys =
ExecIndexBuildScanKeys((PlanState *) indexstate,
node->indexqual,
node->indexstrategy,
node->indexsubtype,
&runtimeKeyInfo,
&scanKeys,
&numScanKeys);
indexstate->biss_RuntimeKeyInfo = runtimeKeyInfo;
indexstate->biss_ScanKeys = scanKeys;
indexstate->biss_NumScanKeys = numScanKeys;
/*
* If we have runtime keys, we need an ExprContext to evaluate them. We
* could just create a "standard" plan node exprcontext, but to keep the
* code looking similar to nodeIndexscan.c, it seems better to stick with
* the approach of using a separate ExprContext.
*/
if (have_runtime_keys)
{
ExprContext *stdecontext = indexstate->ss.ps.ps_ExprContext;
ExecAssignExprContext(estate, &indexstate->ss.ps);
indexstate->biss_RuntimeContext = indexstate->ss.ps.ps_ExprContext;
indexstate->ss.ps.ps_ExprContext = stdecontext;
}
else
{
indexstate->biss_RuntimeContext = NULL;
}
/*
* We do not open or lock the base relation here. We assume that an
* ancestor BitmapHeapScan node is holding AccessShareLock on the heap
* relation throughout the execution of the plan tree.
*/
indexstate->ss.ss_currentRelation = NULL;
indexstate->ss.ss_currentScanDesc = NULL;
/*
* open the index relation and initialize relation and scan descriptors.
* Note we acquire no locks here; the index machinery does its own locks
* and unlocks.
*/
indexstate->biss_RelationDesc = index_open(node->indexid);
indexstate->biss_ScanDesc =
index_beginscan_multi(indexstate->biss_RelationDesc,
estate->es_snapshot,
numScanKeys,
scanKeys);
if (node->indexam == BITMAP_AM_OID)
{
indexstate->odbiss_ScanDesc =
index_beginscan_bitmapwords(indexstate->biss_RelationDesc,
estate->es_snapshot,
numScanKeys,
scanKeys);
node->inmem = false;
} else
{
indexstate->odbiss_ScanDesc = NULL;
node->inmem = true;
}
/*
* all done.
*/
return indexstate;
}
