示例#1
0
/* ----------------------------------------------------------------
 *		ExecInitIndexScan
 *
 *		Initializes the index scan's state information, creates
 *		scan keys, and opens the base and index relations.
 *
 *		Note: index scans have 2 sets of state information because
 *			  we have to keep track of the base relation and the
 *			  index relation.
 * ----------------------------------------------------------------
 */
IndexScanState *
ExecInitIndexScan(IndexScan *node, EState *estate, int eflags)
{
	IndexScanState *indexstate;
	Relation	currentRelation;
	bool		relistarget;

	/*
	 * create state structure
	 */
	indexstate = makeNode(IndexScanState);
	indexstate->ss.ps.plan = (Plan *) node;
	indexstate->ss.ps.state = estate;

	/*
	 * Miscellaneous initialization
	 *
	 * create expression context for node
	 */
	ExecAssignExprContext(estate, &indexstate->ss.ps);

	indexstate->ss.ps.ps_TupFromTlist = false;

	/*
	 * initialize child expressions
	 *
	 * Note: we don't initialize all of the indexqual expression, only the
	 * sub-parts corresponding to runtime keys (see below).  Likewise for
	 * indexorderby, if any.  But the indexqualorig expression is always
	 * initialized even though it will only be used in some uncommon cases ---
	 * would be nice to improve that.  (Problem is that any SubPlans present
	 * in the expression must be found now...)
	 */
	indexstate->ss.ps.targetlist = (List *)
		ExecInitExpr((Expr *) node->scan.plan.targetlist,
					 (PlanState *) indexstate);
	indexstate->ss.ps.qual = (List *)
		ExecInitExpr((Expr *) node->scan.plan.qual,
					 (PlanState *) indexstate);
	indexstate->indexqualorig = (List *)
		ExecInitExpr((Expr *) node->indexqualorig,
					 (PlanState *) indexstate);

	/*
	 * tuple table initialization
	 */
	ExecInitResultTupleSlot(estate, &indexstate->ss.ps);
	ExecInitScanTupleSlot(estate, &indexstate->ss);

	/*
	 * open the base relation and acquire appropriate lock on it.
	 */
	currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid);

	indexstate->ss.ss_currentRelation = currentRelation;
	indexstate->ss.ss_currentScanDesc = NULL;	/* no heap scan here */

	/*
	 * get the scan type from the relation descriptor.
	 */
	ExecAssignScanType(&indexstate->ss, RelationGetDescr(currentRelation));

	/*
	 * Initialize result tuple type and projection info.
	 */
	ExecAssignResultTypeFromTL(&indexstate->ss.ps);
	ExecAssignScanProjectionInfo(&indexstate->ss);

	/*
	 * 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->iss_RelationDesc = index_open(node->indexid,
									 relistarget ? NoLock : AccessShareLock);

	/*
	 * Initialize index-specific scan state
	 */
	indexstate->iss_RuntimeKeysReady = false;
	indexstate->iss_RuntimeKeys = NULL;
	indexstate->iss_NumRuntimeKeys = 0;

	/*
	 * build the index scan keys from the index qualification
	 */
	ExecIndexBuildScanKeys((PlanState *) indexstate,
						   indexstate->iss_RelationDesc,
						   node->scan.scanrelid,
						   node->indexqual,
						   false,
						   &indexstate->iss_ScanKeys,
						   &indexstate->iss_NumScanKeys,
						   &indexstate->iss_RuntimeKeys,
						   &indexstate->iss_NumRuntimeKeys,
						   NULL,	/* no ArrayKeys */
						   NULL);

	/*
	 * any ORDER BY exprs have to be turned into scankeys in the same way
	 */
	ExecIndexBuildScanKeys((PlanState *) indexstate,
						   indexstate->iss_RelationDesc,
						   node->scan.scanrelid,
						   node->indexorderby,
						   true,
						   &indexstate->iss_OrderByKeys,
						   &indexstate->iss_NumOrderByKeys,
						   &indexstate->iss_RuntimeKeys,
						   &indexstate->iss_NumRuntimeKeys,
						   NULL,	/* no ArrayKeys */
						   NULL);

	/*
	 * If we have runtime keys, we need an ExprContext to evaluate them. The
	 * node's standard context won't do because we want to reset that context
	 * for every tuple.  So, build another context just like the other one...
	 * -tgl 7/11/00
	 */
	if (indexstate->iss_NumRuntimeKeys != 0)
	{
		ExprContext *stdecontext = indexstate->ss.ps.ps_ExprContext;

		ExecAssignExprContext(estate, &indexstate->ss.ps);
		indexstate->iss_RuntimeContext = indexstate->ss.ps.ps_ExprContext;
		indexstate->ss.ps.ps_ExprContext = stdecontext;
	}
	else
	{
		indexstate->iss_RuntimeContext = NULL;
	}

	/*
	 * Initialize scan descriptor.
	 */
	indexstate->iss_ScanDesc = index_beginscan(currentRelation,
											   indexstate->iss_RelationDesc,
											   estate->es_snapshot,
											   indexstate->iss_NumScanKeys,
											 indexstate->iss_NumOrderByKeys);

	/*
	 * If no run-time keys to calculate, go ahead and pass the scankeys to the
	 * index AM.
	 */
	if (indexstate->iss_NumRuntimeKeys == 0)
		index_rescan(indexstate->iss_ScanDesc,
					 indexstate->iss_ScanKeys, indexstate->iss_NumScanKeys,
				indexstate->iss_OrderByKeys, indexstate->iss_NumOrderByKeys);

	/*
	 * all done.
	 */
	return indexstate;
}
示例#2
0
/* ----------------------------------------------------------------
 *		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).
	 */

	/*
	 * 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;
	indexstate->biss_RuntimeKeys = NULL;
	indexstate->biss_NumRuntimeKeys = 0;

	/*
	 * build the index scan keys from the index qualification
	 */
	ExecIndexBuildScanKeys((PlanState *) indexstate,
						   indexstate->biss_RelationDesc,
						   node->indexqual,
						   false,
						   &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_bitmap(indexstate->biss_RelationDesc,
							   estate->es_snapshot,
							   indexstate->biss_NumScanKeys);

	/*
	 * If no run-time keys to calculate, go ahead and pass the scankeys to the
	 * index AM.
	 */
	if (indexstate->biss_NumRuntimeKeys == 0 &&
		indexstate->biss_NumArrayKeys == 0)
		index_rescan(indexstate->biss_ScanDesc,
					 indexstate->biss_ScanKeys, indexstate->biss_NumScanKeys,
					 NULL, 0);

	/*
	 * all done.
	 */
	return indexstate;
}
/* ----------------------------------------------------------------
 *		ExecInitIndexOnlyScan
 *
 *		Initializes the index scan's state information, creates
 *		scan keys, and opens the base and index relations.
 *
 *		Note: index scans have 2 sets of state information because
 *			  we have to keep track of the base relation and the
 *			  index relation.
 * ----------------------------------------------------------------
 */
IndexOnlyScanState *
ExecInitIndexOnlyScan(IndexOnlyScan *node, EState *estate, int eflags)
{
	IndexOnlyScanState *indexstate;
	Relation	currentRelation;
	bool		relistarget;
	TupleDesc	tupDesc;

	/*
	 * create state structure
	 */
	indexstate = makeNode(IndexOnlyScanState);
	indexstate->ss.ps.plan = (Plan *) node;
	indexstate->ss.ps.state = estate;
	indexstate->ioss_HeapFetches = 0;

	/*
	 * Miscellaneous initialization
	 *
	 * create expression context for node
	 */
	ExecAssignExprContext(estate, &indexstate->ss.ps);

	indexstate->ss.ps.ps_TupFromTlist = false;

	/*
	 * initialize child expressions
	 *
	 * Note: we don't initialize all of the indexorderby expression, only the
	 * sub-parts corresponding to runtime keys (see below).
	 */
	indexstate->ss.ps.targetlist = (List *)
		ExecInitExpr((Expr *) node->scan.plan.targetlist,
					 (PlanState *) indexstate);
	indexstate->ss.ps.qual = (List *)
		ExecInitExpr((Expr *) node->scan.plan.qual,
					 (PlanState *) indexstate);
	indexstate->indexqual = (List *)
		ExecInitExpr((Expr *) node->indexqual,
					 (PlanState *) indexstate);

	/*
	 * tuple table initialization
	 */
	ExecInitResultTupleSlot(estate, &indexstate->ss.ps);
	ExecInitScanTupleSlot(estate, &indexstate->ss);

	/*
	 * open the base relation and acquire appropriate lock on it.
	 */
	currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid, eflags);

	indexstate->ss.ss_currentRelation = currentRelation;
	indexstate->ss.ss_currentScanDesc = NULL;	/* no heap scan here */

	/*
	 * Build the scan tuple type using the indextlist generated by the
	 * planner.  We use this, rather than the index's physical tuple
	 * descriptor, because the latter contains storage column types not the
	 * types of the original datums.  (It's the AM's responsibility to return
	 * suitable data anyway.)
	 */
	tupDesc = ExecTypeFromTL(node->indextlist, false);
	ExecAssignScanType(&indexstate->ss, tupDesc);

	/*
	 * Initialize result tuple type and projection info.  The node's
	 * targetlist will contain Vars with varno = INDEX_VAR, referencing the
	 * scan tuple.
	 */
	ExecAssignResultTypeFromTL(&indexstate->ss.ps);
	ExecAssignScanProjectionInfoWithVarno(&indexstate->ss, INDEX_VAR);

	/*
	 * 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->ioss_RelationDesc = index_open(node->indexid,
									 relistarget ? NoLock : AccessShareLock);

	/*
	 * Initialize index-specific scan state
	 */
	indexstate->ioss_RuntimeKeysReady = false;
	indexstate->ioss_RuntimeKeys = NULL;
	indexstate->ioss_NumRuntimeKeys = 0;

	/*
	 * build the index scan keys from the index qualification
	 */
	ExecIndexBuildScanKeys((PlanState *) indexstate,
						   indexstate->ioss_RelationDesc,
						   node->indexqual,
						   false,
						   &indexstate->ioss_ScanKeys,
						   &indexstate->ioss_NumScanKeys,
						   &indexstate->ioss_RuntimeKeys,
						   &indexstate->ioss_NumRuntimeKeys,
						   NULL,	/* no ArrayKeys */
						   NULL);

	/*
	 * any ORDER BY exprs have to be turned into scankeys in the same way
	 */
	ExecIndexBuildScanKeys((PlanState *) indexstate,
						   indexstate->ioss_RelationDesc,
						   node->indexorderby,
						   true,
						   &indexstate->ioss_OrderByKeys,
						   &indexstate->ioss_NumOrderByKeys,
						   &indexstate->ioss_RuntimeKeys,
						   &indexstate->ioss_NumRuntimeKeys,
						   NULL,	/* no ArrayKeys */
						   NULL);

	/*
	 * If we have runtime keys, we need an ExprContext to evaluate them. The
	 * node's standard context won't do because we want to reset that context
	 * for every tuple.  So, build another context just like the other one...
	 * -tgl 7/11/00
	 */
	if (indexstate->ioss_NumRuntimeKeys != 0)
	{
		ExprContext *stdecontext = indexstate->ss.ps.ps_ExprContext;

		ExecAssignExprContext(estate, &indexstate->ss.ps);
		indexstate->ioss_RuntimeContext = indexstate->ss.ps.ps_ExprContext;
		indexstate->ss.ps.ps_ExprContext = stdecontext;
	}
	else
	{
		indexstate->ioss_RuntimeContext = NULL;
	}

	/*
	 * Initialize scan descriptor.
	 */
	indexstate->ioss_ScanDesc = index_beginscan(currentRelation,
												indexstate->ioss_RelationDesc,
												estate->es_snapshot,
												indexstate->ioss_NumScanKeys,
											indexstate->ioss_NumOrderByKeys);

	/* Set it up for index-only scan */
	indexstate->ioss_ScanDesc->xs_want_itup = true;
	indexstate->ioss_VMBuffer = InvalidBuffer;

	/*
	 * If no run-time keys to calculate, go ahead and pass the scankeys to the
	 * index AM.
	 */
	if (indexstate->ioss_NumRuntimeKeys == 0)
		index_rescan(indexstate->ioss_ScanDesc,
					 indexstate->ioss_ScanKeys,
					 indexstate->ioss_NumScanKeys,
					 indexstate->ioss_OrderByKeys,
					 indexstate->ioss_NumOrderByKeys);

	/*
	 * all done.
	 */
	return indexstate;
}
示例#4
0
/* ----------------------------------------------------------------
 *		ExecInitIndexScan
 *
 *		Initializes the index scan's state information, creates
 *		scan keys, and opens the base and index relations.
 *
 *		Note: index scans have 2 sets of state information because
 *			  we have to keep track of the base relation and the
 *			  index relation.
 * ----------------------------------------------------------------
 */
IndexScanState *
ExecInitIndexScan(IndexScan *node, EState *estate, int eflags)
{
    IndexScanState *indexstate;
    Relation	currentRelation;
    bool		relistarget;

    /*
     * create state structure
     */
    indexstate = makeNode(IndexScanState);
    indexstate->ss.ps.plan = (Plan *) node;
    indexstate->ss.ps.state = estate;

    /*
     * Miscellaneous initialization
     *
     * create expression context for node
     */
    ExecAssignExprContext(estate, &indexstate->ss.ps);

    /*indexstate->ss.ps.ps_TupFromTlist = false;*/

    /*
     * initialize child expressions
     *
     * Note: we don't initialize all of the indexqual expression, only the
     * sub-parts corresponding to runtime keys (see below).  The indexqualorig
     * expression is always initialized even though it will only be used in
     * some uncommon cases --- would be nice to improve that.  (Problem is
     * that any SubPlans present in the expression must be found now...)
     */
    indexstate->ss.ps.targetlist = (List *)
                                   ExecInitExpr((Expr *) node->scan.plan.targetlist,
                                           (PlanState *) indexstate);
    indexstate->ss.ps.qual = (List *)
                             ExecInitExpr((Expr *) node->scan.plan.qual,
                                          (PlanState *) indexstate);
    indexstate->indexqualorig = (List *)
                                ExecInitExpr((Expr *) node->indexqualorig,
                                        (PlanState *) indexstate);

#define INDEXSCAN_NSLOTS 2

    /*
     * tuple table initialization
     */
    ExecInitResultTupleSlot(estate, &indexstate->ss.ps);
    ExecInitScanTupleSlot(estate, &indexstate->ss);

    /*
     * open the base relation and acquire appropriate lock on it.
     */
    currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid);

    indexstate->ss.ss_currentRelation = currentRelation;

    /*
     * get the scan type from the relation descriptor.
     */
    ExecAssignScanType(&indexstate->ss, RelationGetDescr(currentRelation));

    /*
     * 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->iss_RelationDesc = index_open(node->indexid,
                                   relistarget ? NoLock : AccessShareLock);

    /*
     * build the index scan keys from the index qualification
     */
    ExecIndexBuildScanKeys((PlanState *) indexstate,
                           indexstate->iss_RelationDesc,
                           node->indexqual,
                           node->indexstrategy,
                           node->indexsubtype,
                           &indexstate->iss_ScanKeys,
                           &indexstate->iss_NumScanKeys,
                           &indexstate->iss_RuntimeKeys,
                           &indexstate->iss_NumRuntimeKeys,
                           NULL,	/* no ArrayKeys */
                           NULL);

    /*
     * If we have runtime keys, we need an ExprContext to evaluate them. The
     * node's standard context won't do because we want to reset that context
     * for every tuple.  So, build another context just like the other one...
     * -tgl 7/11/00
     */
    if (indexstate->iss_NumRuntimeKeys != 0)
    {
        ExprContext *stdecontext = indexstate->ss.ps.ps_ExprContext;

        ExecAssignExprContext(estate, &indexstate->ss.ps);
        indexstate->iss_RuntimeContext = indexstate->ss.ps.ps_ExprContext;
        indexstate->ss.ps.ps_ExprContext = stdecontext;
    }
    else
    {
        indexstate->iss_RuntimeContext = NULL;
    }

    /*
     * Initialize index-specific scan state
     */
    indexstate->iss_RuntimeKeysReady = false;

    /*
     * Initialize result tuple type and projection info.
     */
    ExecAssignResultTypeFromTL(&indexstate->ss.ps);
    ExecAssignScanProjectionInfo(&indexstate->ss);

    initGpmonPktForIndexScan((Plan *)node, &indexstate->ss.ps.gpmon_pkt, estate);

    /*
     * If eflag contains EXEC_FLAG_REWIND or EXEC_FLAG_BACKWARD or EXEC_FLAG_MARK,
     * then this node is not eager free safe.
     */
    indexstate->ss.ps.delayEagerFree =
        ((eflags & (EXEC_FLAG_REWIND | EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK)) != 0);

    /*
     * all done.
     */
    return indexstate;
}
/*
 * This function initializes a part and returns true if a new index has been prepared for scanning.
 */
static bool
initNextIndexToScan(DynamicIndexScanState *node)
{
	IndexScanState *indexState = &(node->indexScanState);

	DynamicIndexScan *dynamicIndexScan = (DynamicIndexScan *)node->indexScanState.ss.ps.plan;

	/* Load new index when the scanning of the previous index is done. */
	if (indexState->ss.scan_state == SCAN_INIT ||
		indexState->ss.scan_state == SCAN_DONE)
	{
		/* This is the oid of a partition of the table (*not* index) */
		Oid *pid = hash_seq_search(&node->pidxStatus);
		if (pid == NULL)
		{
			/* Return if all parts have been scanned. */
			node->shouldCallHashSeqTerm = false;
			return false;
		}

		/* Collect number of partitions scanned in EXPLAIN ANALYZE */
		if(NULL != indexState->ss.ps.instrument)
		{
			Instrumentation *instr = indexState->ss.ps.instrument;
			instr->numPartScanned ++;
		}

		DynamicIndexScan_ReMapColumns(node, *pid);

		/*
		 * The is the oid of the partition of an *index*. Note: a partitioned table
		 * has a root and a set of partitions (may be multi-level). An index
		 * on a partitioned table also has a root and a set of index partitions.
		 * We started at table level, and now we are fetching the oid of an index
		 * partition.
		 */
		Oid pindex = getPhysicalIndexRelid(dynamicIndexScan->logicalIndexInfo,
					 *pid);

		Assert(OidIsValid(pindex));

		Relation currentRelation = OpenScanRelationByOid(*pid);
		indexState->ss.ss_currentRelation = currentRelation;

		for (int i=0; i < DYNAMICINDEXSCAN_NSLOTS; i++)
		{
			indexState->ss.ss_ScanTupleSlot[i].tts_tableOid = *pid;
		}

		ExecAssignScanType(&indexState->ss, RelationGetDescr(currentRelation));

		ScanState *scanState = (ScanState *)node;

		MemoryContextReset(node->partitionMemoryContext);
		MemoryContext oldCxt = MemoryContextSwitchTo(node->partitionMemoryContext);

		/* Initialize child expressions */
		scanState->ps.qual = (List *)ExecInitExpr((Expr *)scanState->ps.plan->qual, (PlanState*)scanState);
		scanState->ps.targetlist = (List *)ExecInitExpr((Expr *)scanState->ps.plan->targetlist, (PlanState*)scanState);

		ExecAssignScanProjectionInfo(scanState);

		EState *estate = indexState->ss.ps.state;

		indexState->iss_RelationDesc =
			OpenIndexRelation(estate, pindex, *pid);

		/*
		 * build the index scan keys from the index qualification
		 */
		ExecIndexBuildScanKeys((PlanState *) indexState,
						   indexState->iss_RelationDesc,
						   dynamicIndexScan->indexqual,
						   dynamicIndexScan->indexstrategy,
						   dynamicIndexScan->indexsubtype,
						   &indexState->iss_ScanKeys,
						   &indexState->iss_NumScanKeys,
						   &indexState->iss_RuntimeKeys,
						   &indexState->iss_NumRuntimeKeys,
						   NULL,
						   NULL);

		MemoryContextSwitchTo(oldCxt);

		ExprContext *econtext = indexState->iss_RuntimeContext;		/* context for runtime keys */

		if (indexState->iss_NumRuntimeKeys != 0)
		{
			ExecIndexEvalRuntimeKeys(econtext,
									 indexState->iss_RuntimeKeys,
									 indexState->iss_NumRuntimeKeys);
		}

		indexState->iss_RuntimeKeysReady = true;

		/*
		 * Initialize result tuple type and projection info.
		 */
		TupleDesc td = indexState->ss.ps.ps_ResultTupleSlot->tts_tupleDescriptor;
		if (td)
		{
			pfree(td);
			td = NULL;
		}
		ExecAssignResultTypeFromTL(&indexState->ss.ps);
		ExecAssignScanProjectionInfo(&indexState->ss);

		indexState->iss_ScanDesc = index_beginscan(currentRelation,
				indexState->iss_RelationDesc,
				estate->es_snapshot,
				indexState->iss_NumScanKeys,
				indexState->iss_ScanKeys);

		indexState->ss.scan_state = SCAN_SCAN;
	}

	return true;
}
示例#6
0
/* ----------------------------------------------------------------
 *		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;
}