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Postgres95 1.01 Distribution - Virgin Sources
This commit is contained in:
902
src/backend/executor/nodeIndexscan.c
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902
src/backend/executor/nodeIndexscan.c
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@ -0,0 +1,902 @@
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/*-------------------------------------------------------------------------
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*
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* nodeIndexscan.c--
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* Routines to support indexes and indexed scans of relations
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*
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* Copyright (c) 1994, Regents of the University of California
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*
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||||
*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/executor/nodeIndexscan.c,v 1.1.1.1 1996/07/09 06:21:26 scrappy Exp $
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*
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*-------------------------------------------------------------------------
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*/
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/*
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* INTERFACE ROUTINES
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* ExecInsertIndexTuples inserts tuples into indices on result relation
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*
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* ExecIndexScan scans a relation using indices
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* ExecIndexNext using index to retrieve next tuple
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* ExecInitIndexScan creates and initializes state info.
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* ExecIndexReScan rescans the indexed relation.
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* ExecEndIndexScan releases all storage.
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* ExecIndexMarkPos marks scan position.
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* ExecIndexRestrPos restores scan position.
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*
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* NOTES
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* the code supporting ExecInsertIndexTuples should be
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* collected and merged with the genam stuff.
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*
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*/
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#include "executor/executor.h"
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#include "executor/nodeIndexscan.h"
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#include "optimizer/clauses.h" /* for get_op, get_leftop, get_rightop */
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#include "parser/parsetree.h" /* for rt_fetch() */
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#include "access/skey.h"
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#include "utils/palloc.h"
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#include "catalog/index.h"
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#include "storage/bufmgr.h"
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#include "storage/lmgr.h"
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#include "nodes/nodeFuncs.h"
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/* ----------------
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||||
* Misc stuff to move to executor.h soon -cim 6/5/90
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* ----------------
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*/
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#define NO_OP 0
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#define LEFT_OP 1
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#define RIGHT_OP 2
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static TupleTableSlot *IndexNext(IndexScan *node);
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||||
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/* ----------------------------------------------------------------
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* IndexNext
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*
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* Retrieve a tuple from the IndexScan node's currentRelation
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* using the indices in the IndexScanState information.
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*
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* note: the old code mentions 'Primary indices'. to my knowledge
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* we only support a single secondary index. -cim 9/11/89
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*
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* old comments:
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* retrieve a tuple from relation using the indices given.
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* The indices are used in the order they appear in 'indices'.
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* The indices may be primary or secondary indices:
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* * primary index -- scan the relation 'relID' using keys supplied.
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* * secondary index -- scan the index relation to get the 'tid' for
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* a tuple in the relation 'relID'.
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* If the current index(pointed by 'indexPtr') fails to return a
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* tuple, the next index in the indices is used.
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*
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* bug fix so that it should retrieve on a null scan key.
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* ----------------------------------------------------------------
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*/
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static TupleTableSlot *
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IndexNext(IndexScan *node)
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{
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EState *estate;
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CommonScanState *scanstate;
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IndexScanState *indexstate;
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ScanDirection direction;
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int indexPtr;
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IndexScanDescPtr scanDescs;
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IndexScanDesc scandesc;
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Relation heapRelation;
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RetrieveIndexResult result;
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ItemPointer iptr;
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HeapTuple tuple;
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TupleTableSlot *slot;
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Buffer buffer = InvalidBuffer;
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/* ----------------
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* extract necessary information from index scan node
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* ----------------
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*/
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estate = node->scan.plan.state;
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direction = estate->es_direction;
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scanstate = node->scan.scanstate;
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indexstate = node->indxstate;
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indexPtr = indexstate->iss_IndexPtr;
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scanDescs = indexstate->iss_ScanDescs;
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scandesc = scanDescs[ indexPtr ];
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heapRelation = scanstate->css_currentRelation;
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slot = scanstate->css_ScanTupleSlot;
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/* ----------------
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* ok, now that we have what we need, fetch an index tuple.
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* ----------------
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*/
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for(;;) {
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result = index_getnext(scandesc, direction);
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/* ----------------
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||||
* if scanning this index succeeded then return the
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* appropriate heap tuple.. else return NULL.
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* ----------------
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*/
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||||
if (result) {
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iptr = &result->heap_iptr;
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tuple = heap_fetch(heapRelation,
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NowTimeQual,
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iptr,
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&buffer);
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/* be tidy */
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pfree(result);
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if (tuple == NULL) {
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||||
/* ----------------
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||||
* we found a deleted tuple, so keep on scanning..
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* ----------------
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*/
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if (BufferIsValid(buffer))
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ReleaseBuffer(buffer);
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continue;
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}
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/* ----------------
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* store the scanned tuple in the scan tuple slot of
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* the scan state. Eventually we will only do this and not
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* return a tuple. Note: we pass 'false' because tuples
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* returned by amgetnext are pointers onto disk pages and
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||||
* were not created with palloc() and so should not be pfree()'d.
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* ----------------
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*/
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ExecStoreTuple(tuple, /* tuple to store */
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slot, /* slot to store in */
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buffer, /* buffer associated with tuple */
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false); /* don't pfree */
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||||
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return slot;
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||||
}
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||||
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||||
/* ----------------
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||||
* if we get here it means the index scan failed so we
|
||||
* are at the end of the scan..
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||||
* ----------------
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||||
*/
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||||
return ExecClearTuple(slot);
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||||
}
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||||
}
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||||
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||||
/* ----------------------------------------------------------------
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* ExecIndexScan(node)
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*
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* old comments:
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||||
* Scans the relation using primary or secondary indices and returns
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* the next qualifying tuple in the direction specified.
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* It calls ExecScan() and passes it the access methods which returns
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* the next tuple using the indices.
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*
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||||
* Conditions:
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||||
* -- the "cursor" maintained by the AMI is positioned at the tuple
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||||
* returned previously.
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||||
*
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||||
* Initial States:
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||||
* -- the relation indicated is opened for scanning so that the
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||||
* "cursor" is positioned before the first qualifying tuple.
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||||
* -- all index realtions are opened for scanning.
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||||
* -- indexPtr points to the first index.
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||||
* -- state variable ruleFlag = nil.
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||||
* ----------------------------------------------------------------
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||||
*/
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||||
TupleTableSlot *
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||||
ExecIndexScan(IndexScan *node)
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||||
{
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||||
TupleTableSlot *returnTuple;
|
||||
|
||||
/* ----------------
|
||||
* use IndexNext as access method
|
||||
* ----------------
|
||||
*/
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||||
returnTuple = ExecScan(&node->scan, IndexNext);
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||||
return returnTuple;
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||||
}
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||||
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||||
/* ----------------------------------------------------------------
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||||
* ExecIndexReScan(node)
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||||
*
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||||
* Recalculates the value of the scan keys whose value depends on
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||||
* information known at runtime and rescans the indexed relation.
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||||
* Updating the scan key was formerly done separately in
|
||||
* ExecUpdateIndexScanKeys. Integrating it into ReScan
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||||
* makes rescans of indices and
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||||
* relations/general streams more uniform.
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||||
*
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||||
* ----------------------------------------------------------------
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||||
*/
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||||
void
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||||
ExecIndexReScan(IndexScan *node, ExprContext *exprCtxt, Plan* parent)
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||||
{
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||||
EState *estate;
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||||
IndexScanState *indexstate;
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||||
ScanDirection direction;
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||||
IndexScanDescPtr scanDescs;
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||||
ScanKey *scanKeys;
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||||
IndexScanDesc sdesc;
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||||
ScanKey skey;
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||||
int numIndices;
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||||
int i;
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||||
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||||
Pointer *runtimeKeyInfo;
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||||
int indexPtr;
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||||
int *numScanKeys;
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||||
List *indxqual;
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||||
List *qual;
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||||
int n_keys;
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||||
ScanKey scan_keys;
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||||
int *run_keys;
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||||
int j;
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||||
Expr *clause;
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||||
Node *scanexpr;
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||||
Datum scanvalue;
|
||||
bool isNull;
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||||
bool isDone;
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||||
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||||
indexstate = node->indxstate;
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estate = node->scan.plan.state;
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direction = estate->es_direction;
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indexstate = node->indxstate;
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numIndices = indexstate->iss_NumIndices;
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||||
scanDescs = indexstate->iss_ScanDescs;
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||||
scanKeys = indexstate->iss_ScanKeys;
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||||
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||||
runtimeKeyInfo = (Pointer *) indexstate->iss_RuntimeKeyInfo;
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||||
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if (runtimeKeyInfo != NULL) {
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/*
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||||
* get the index qualifications and
|
||||
* recalculate the appropriate values
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||||
*/
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indexPtr = indexstate->iss_IndexPtr;
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indxqual = node->indxqual;
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qual = nth(indexPtr, indxqual);
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numScanKeys = indexstate->iss_NumScanKeys;
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n_keys = numScanKeys[indexPtr];
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run_keys = (int *) runtimeKeyInfo[indexPtr];
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||||
scan_keys = (ScanKey) scanKeys[indexPtr];
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||||
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||||
for (j=0; j < n_keys; j++) {
|
||||
/*
|
||||
* If we have a run-time key, then extract the run-time
|
||||
* expression and evaluate it with respect to the current
|
||||
* outer tuple. We then stick the result into the scan
|
||||
* key.
|
||||
*/
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if (run_keys[j] != NO_OP) {
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clause = nth(j, qual);
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scanexpr = (run_keys[j] == RIGHT_OP) ?
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(Node*) get_rightop(clause) : (Node*) get_leftop(clause) ;
|
||||
/* pass in isDone but ignore it. We don't iterate in quals */
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||||
scanvalue = (Datum)
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||||
ExecEvalExpr(scanexpr, exprCtxt, &isNull, &isDone);
|
||||
scan_keys[j].sk_argument = scanvalue;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* rescans all indices
|
||||
*
|
||||
* note: AMrescan assumes only one scan key. This may have
|
||||
* to change if we ever decide to support multiple keys.
|
||||
*/
|
||||
for (i = 0; i < numIndices; i++) {
|
||||
sdesc = scanDescs[ i ];
|
||||
skey = scanKeys[ i ];
|
||||
index_rescan(sdesc, direction, skey);
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* perhaps return something meaningful
|
||||
* ----------------
|
||||
*/
|
||||
return;
|
||||
}
|
||||
|
||||
/* ----------------------------------------------------------------
|
||||
* ExecEndIndexScan
|
||||
*
|
||||
* old comments
|
||||
* Releases any storage allocated through C routines.
|
||||
* Returns nothing.
|
||||
* ----------------------------------------------------------------
|
||||
*/
|
||||
void
|
||||
ExecEndIndexScan(IndexScan *node)
|
||||
{
|
||||
CommonScanState *scanstate;
|
||||
IndexScanState *indexstate;
|
||||
ScanKey *scanKeys;
|
||||
int numIndices;
|
||||
int i;
|
||||
|
||||
scanstate = node->scan.scanstate;
|
||||
indexstate = node->indxstate;
|
||||
|
||||
/* ----------------
|
||||
* extract information from the node
|
||||
* ----------------
|
||||
*/
|
||||
numIndices = indexstate->iss_NumIndices;
|
||||
scanKeys = indexstate->iss_ScanKeys;
|
||||
|
||||
/* ----------------
|
||||
* Free the projection info and the scan attribute info
|
||||
*
|
||||
* Note: we don't ExecFreeResultType(scanstate)
|
||||
* because the rule manager depends on the tupType
|
||||
* returned by ExecMain(). So for now, this
|
||||
* is freed at end-transaction time. -cim 6/2/91
|
||||
* ----------------
|
||||
*/
|
||||
ExecFreeProjectionInfo(&scanstate->cstate);
|
||||
|
||||
/* ----------------
|
||||
* close the heap and index relations
|
||||
* ----------------
|
||||
*/
|
||||
ExecCloseR((Plan *) node);
|
||||
|
||||
/* ----------------
|
||||
* free the scan keys used in scanning the indices
|
||||
* ----------------
|
||||
*/
|
||||
for (i=0; i<numIndices; i++) {
|
||||
if (scanKeys[i]!=NULL)
|
||||
pfree(scanKeys[i]);
|
||||
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* clear out tuple table slots
|
||||
* ----------------
|
||||
*/
|
||||
ExecClearTuple(scanstate->cstate.cs_ResultTupleSlot);
|
||||
ExecClearTuple(scanstate->css_ScanTupleSlot);
|
||||
/* ExecClearTuple(scanstate->css_RawTupleSlot); */
|
||||
}
|
||||
|
||||
/* ----------------------------------------------------------------
|
||||
* ExecIndexMarkPos
|
||||
*
|
||||
* old comments
|
||||
* Marks scan position by marking the current index.
|
||||
* Returns nothing.
|
||||
* ----------------------------------------------------------------
|
||||
*/
|
||||
void
|
||||
ExecIndexMarkPos(IndexScan *node)
|
||||
{
|
||||
IndexScanState *indexstate;
|
||||
IndexScanDescPtr indexScanDescs;
|
||||
IndexScanDesc scanDesc;
|
||||
int indexPtr;
|
||||
|
||||
indexstate = node->indxstate;
|
||||
indexPtr = indexstate->iss_IndexPtr;
|
||||
indexScanDescs = indexstate->iss_ScanDescs;
|
||||
scanDesc = indexScanDescs[ indexPtr ];
|
||||
|
||||
/* ----------------
|
||||
* XXX access methods don't return marked positions so
|
||||
* ----------------
|
||||
*/
|
||||
IndexScanMarkPosition( scanDesc );
|
||||
return;
|
||||
}
|
||||
|
||||
/* ----------------------------------------------------------------
|
||||
* ExecIndexRestrPos
|
||||
*
|
||||
* old comments
|
||||
* Restores scan position by restoring the current index.
|
||||
* Returns nothing.
|
||||
*
|
||||
* XXX Assumes previously marked scan position belongs to current index
|
||||
* ----------------------------------------------------------------
|
||||
*/
|
||||
void
|
||||
ExecIndexRestrPos(IndexScan *node)
|
||||
{
|
||||
IndexScanState *indexstate;
|
||||
IndexScanDescPtr indexScanDescs;
|
||||
IndexScanDesc scanDesc;
|
||||
int indexPtr;
|
||||
|
||||
indexstate = node->indxstate;
|
||||
indexPtr = indexstate->iss_IndexPtr;
|
||||
indexScanDescs = indexstate->iss_ScanDescs;
|
||||
scanDesc = indexScanDescs[ indexPtr ];
|
||||
|
||||
IndexScanRestorePosition( scanDesc );
|
||||
}
|
||||
|
||||
/* ----------------------------------------------------------------
|
||||
* 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 relations.
|
||||
*
|
||||
* old comments
|
||||
* Creates the run-time state information for the node and
|
||||
* sets the relation id to contain relevant decriptors.
|
||||
*
|
||||
* Parameters:
|
||||
* node: IndexNode node produced by the planner.
|
||||
* estate: the execution state initialized in InitPlan.
|
||||
* ----------------------------------------------------------------
|
||||
*/
|
||||
bool
|
||||
ExecInitIndexScan(IndexScan *node, EState *estate, Plan *parent)
|
||||
{
|
||||
IndexScanState *indexstate;
|
||||
CommonScanState *scanstate;
|
||||
List *indxqual;
|
||||
List *indxid;
|
||||
int i;
|
||||
int numIndices;
|
||||
int indexPtr;
|
||||
ScanKey *scanKeys;
|
||||
int *numScanKeys;
|
||||
RelationPtr relationDescs;
|
||||
IndexScanDescPtr scanDescs;
|
||||
Pointer *runtimeKeyInfo;
|
||||
bool have_runtime_keys;
|
||||
List *rangeTable;
|
||||
RangeTblEntry *rtentry;
|
||||
Index relid;
|
||||
Oid reloid;
|
||||
TimeQual timeQual;
|
||||
|
||||
Relation currentRelation;
|
||||
HeapScanDesc currentScanDesc;
|
||||
ScanDirection direction;
|
||||
int baseid;
|
||||
|
||||
/* ----------------
|
||||
* assign execution state to node
|
||||
* ----------------
|
||||
*/
|
||||
node->scan.plan.state = estate;
|
||||
|
||||
/* --------------------------------
|
||||
* Part 1) initialize scan state
|
||||
*
|
||||
* create new CommonScanState for node
|
||||
* --------------------------------
|
||||
*/
|
||||
scanstate = makeNode(CommonScanState);
|
||||
/*
|
||||
scanstate->ss_ProcOuterFlag = false;
|
||||
scanstate->ss_OldRelId = 0;
|
||||
*/
|
||||
|
||||
node->scan.scanstate = scanstate;
|
||||
|
||||
/* ----------------
|
||||
* assign node's base_id .. we don't use AssignNodeBaseid() because
|
||||
* the increment is done later on after we assign the index scan's
|
||||
* scanstate. see below.
|
||||
* ----------------
|
||||
*/
|
||||
baseid = estate->es_BaseId;
|
||||
/* scanstate->csstate.cstate.bnode.base_id = baseid; */
|
||||
scanstate->cstate.cs_base_id = baseid;
|
||||
|
||||
/* ----------------
|
||||
* create expression context for node
|
||||
* ----------------
|
||||
*/
|
||||
ExecAssignExprContext(estate, &scanstate->cstate);
|
||||
|
||||
#define INDEXSCAN_NSLOTS 3
|
||||
/* ----------------
|
||||
* tuple table initialization
|
||||
* ----------------
|
||||
*/
|
||||
ExecInitResultTupleSlot(estate, &scanstate->cstate);
|
||||
ExecInitScanTupleSlot(estate, scanstate);
|
||||
/* ExecInitRawTupleSlot(estate, scanstate); */
|
||||
|
||||
/* ----------------
|
||||
* initialize projection info. result type comes from scan desc
|
||||
* below..
|
||||
* ----------------
|
||||
*/
|
||||
ExecAssignProjectionInfo((Plan *) node, &scanstate->cstate);
|
||||
|
||||
/* --------------------------------
|
||||
* Part 2) initialize index scan state
|
||||
*
|
||||
* create new IndexScanState for node
|
||||
* --------------------------------
|
||||
*/
|
||||
indexstate = makeNode(IndexScanState);
|
||||
indexstate->iss_NumIndices = 0;
|
||||
indexstate->iss_IndexPtr = 0;
|
||||
indexstate->iss_ScanKeys = NULL;
|
||||
indexstate->iss_NumScanKeys = NULL;
|
||||
indexstate->iss_RuntimeKeyInfo = NULL;
|
||||
indexstate->iss_RelationDescs = NULL;
|
||||
indexstate->iss_ScanDescs = NULL;
|
||||
|
||||
node->indxstate = indexstate;
|
||||
|
||||
/* ----------------
|
||||
* assign base id to index scan state also
|
||||
* ----------------
|
||||
*/
|
||||
indexstate->cstate.cs_base_id = baseid;
|
||||
baseid++;
|
||||
estate->es_BaseId = baseid;
|
||||
|
||||
/* ----------------
|
||||
* get the index node information
|
||||
* ----------------
|
||||
*/
|
||||
indxid = node->indxid;
|
||||
indxqual = node->indxqual;
|
||||
numIndices = length(indxid);
|
||||
indexPtr = 0;
|
||||
|
||||
CXT1_printf("ExecInitIndexScan: context is %d\n", CurrentMemoryContext);
|
||||
|
||||
/* ----------------
|
||||
* scanKeys is used to keep track of the ScanKey's. This is needed
|
||||
* because a single scan may use several indices and each index has
|
||||
* its own ScanKey.
|
||||
* ----------------
|
||||
*/
|
||||
numScanKeys = (int *) palloc(numIndices * sizeof(int));
|
||||
scanKeys = (ScanKey *) palloc(numIndices * sizeof(ScanKey));
|
||||
relationDescs = (RelationPtr) palloc(numIndices * sizeof(Relation));
|
||||
scanDescs = (IndexScanDescPtr) palloc(numIndices * sizeof(IndexScanDesc));
|
||||
|
||||
/* ----------------
|
||||
* initialize runtime key info.
|
||||
* ----------------
|
||||
*/
|
||||
have_runtime_keys = false;
|
||||
runtimeKeyInfo = (Pointer *)
|
||||
palloc(numIndices * sizeof(Pointer));
|
||||
|
||||
/* ----------------
|
||||
* build the index scan keys from the index qualification
|
||||
* ----------------
|
||||
*/
|
||||
for (i=0; i < numIndices; i++) {
|
||||
int j;
|
||||
List *qual;
|
||||
int n_keys;
|
||||
ScanKey scan_keys;
|
||||
int *run_keys;
|
||||
|
||||
qual = nth(i, indxqual);
|
||||
n_keys = length(qual);
|
||||
scan_keys = (n_keys <= 0) ? NULL :
|
||||
(ScanKey)palloc(n_keys * sizeof(ScanKeyData));
|
||||
|
||||
CXT1_printf("ExecInitIndexScan: context is %d\n",
|
||||
CurrentMemoryContext);
|
||||
|
||||
if (n_keys > 0) {
|
||||
run_keys = (int *) palloc(n_keys * sizeof(int));
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* for each opclause in the given qual,
|
||||
* convert each qual's opclause into a single scan key
|
||||
* ----------------
|
||||
*/
|
||||
for (j=0; j < n_keys; j++) {
|
||||
Expr *clause; /* one part of index qual */
|
||||
Oper *op; /* operator used in scan.. */
|
||||
Node *leftop; /* expr on lhs of operator */
|
||||
Node *rightop; /* expr on rhs ... */
|
||||
|
||||
int scanvar; /* which var identifies varattno */
|
||||
AttrNumber varattno; /* att number used in scan */
|
||||
Oid opid; /* operator id used in scan */
|
||||
Datum scanvalue; /* value used in scan (if const) */
|
||||
|
||||
/* ----------------
|
||||
* extract clause information from the qualification
|
||||
* ----------------
|
||||
*/
|
||||
clause = nth(j, qual);
|
||||
|
||||
op = (Oper*)clause->oper;
|
||||
if (!IsA(op,Oper))
|
||||
elog(WARN, "ExecInitIndexScan: op not an Oper!");
|
||||
|
||||
opid = op->opid;
|
||||
|
||||
/* ----------------
|
||||
* Here we figure out the contents of the index qual.
|
||||
* The usual case is (op var const) or (op const var)
|
||||
* which means we form a scan key for the attribute
|
||||
* listed in the var node and use the value of the const.
|
||||
*
|
||||
* If we don't have a const node, then it means that
|
||||
* one of the var nodes refers to the "scan" tuple and
|
||||
* is used to determine which attribute to scan, and the
|
||||
* other expression is used to calculate the value used in
|
||||
* scanning the index.
|
||||
*
|
||||
* This means our index scan's scan key is a function of
|
||||
* information obtained during the execution of the plan
|
||||
* in which case we need to recalculate the index scan key
|
||||
* at run time.
|
||||
*
|
||||
* Hence, we set have_runtime_keys to true and then set
|
||||
* the appropriate flag in run_keys to LEFT_OP or RIGHT_OP.
|
||||
* The corresponding scan keys are recomputed at run time.
|
||||
* ----------------
|
||||
*/
|
||||
|
||||
scanvar = NO_OP;
|
||||
|
||||
/* ----------------
|
||||
* determine information in leftop
|
||||
* ----------------
|
||||
*/
|
||||
leftop = (Node*) get_leftop(clause);
|
||||
|
||||
if (IsA(leftop,Var) && var_is_rel((Var*)leftop)) {
|
||||
/* ----------------
|
||||
* if the leftop is a "rel-var", then it means
|
||||
* that it is a var node which tells us which
|
||||
* attribute to use for our scan key.
|
||||
* ----------------
|
||||
*/
|
||||
varattno = ((Var*) leftop)->varattno;
|
||||
scanvar = LEFT_OP;
|
||||
} else if (IsA(leftop,Const)) {
|
||||
/* ----------------
|
||||
* if the leftop is a const node then it means
|
||||
* it identifies the value to place in our scan key.
|
||||
* ----------------
|
||||
*/
|
||||
run_keys[ j ] = NO_OP;
|
||||
scanvalue = ((Const*) leftop)->constvalue;
|
||||
} else if (leftop != NULL &&
|
||||
is_funcclause(leftop) &&
|
||||
var_is_rel(lfirst(((Expr*)leftop)->args))) {
|
||||
/* ----------------
|
||||
* if the leftop is a func node then it means
|
||||
* it identifies the value to place in our scan key.
|
||||
* Since functional indices have only one attribute
|
||||
* the attno must always be set to 1.
|
||||
* ----------------
|
||||
*/
|
||||
varattno = 1;
|
||||
scanvar = LEFT_OP;
|
||||
|
||||
} else {
|
||||
/* ----------------
|
||||
* otherwise, the leftop contains information usable
|
||||
* at runtime to figure out the value to place in our
|
||||
* scan key.
|
||||
* ----------------
|
||||
*/
|
||||
have_runtime_keys = true;
|
||||
run_keys[ j ] = LEFT_OP;
|
||||
scanvalue = Int32GetDatum((int32) true);
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* now determine information in rightop
|
||||
* ----------------
|
||||
*/
|
||||
rightop = (Node*) get_rightop(clause);
|
||||
|
||||
if (IsA(rightop,Var) && var_is_rel((Var*)rightop)) {
|
||||
/* ----------------
|
||||
* here we make sure only one op identifies the
|
||||
* scan-attribute...
|
||||
* ----------------
|
||||
*/
|
||||
if (scanvar == LEFT_OP)
|
||||
elog(WARN, "ExecInitIndexScan: %s",
|
||||
"both left and right op's are rel-vars");
|
||||
|
||||
/* ----------------
|
||||
* if the rightop is a "rel-var", then it means
|
||||
* that it is a var node which tells us which
|
||||
* attribute to use for our scan key.
|
||||
* ----------------
|
||||
*/
|
||||
varattno = ((Var*) rightop)->varattno;
|
||||
scanvar = RIGHT_OP;
|
||||
|
||||
} else if (IsA(rightop,Const)) {
|
||||
/* ----------------
|
||||
* if the leftop is a const node then it means
|
||||
* it identifies the value to place in our scan key.
|
||||
* ----------------
|
||||
*/
|
||||
run_keys[ j ] = NO_OP;
|
||||
scanvalue = ((Const*) rightop)->constvalue;
|
||||
|
||||
} else if (rightop!=NULL &&
|
||||
is_funcclause(rightop) &&
|
||||
var_is_rel(lfirst(((Expr*)rightop)->args))) {
|
||||
/* ----------------
|
||||
* if the rightop is a func node then it means
|
||||
* it identifies the value to place in our scan key.
|
||||
* Since functional indices have only one attribute
|
||||
* the attno must always be set to 1.
|
||||
* ----------------
|
||||
*/
|
||||
if (scanvar == LEFT_OP)
|
||||
elog(WARN, "ExecInitIndexScan: %s",
|
||||
"both left and right ops are rel-vars");
|
||||
|
||||
varattno = 1;
|
||||
scanvar = RIGHT_OP;
|
||||
|
||||
} else {
|
||||
/* ----------------
|
||||
* otherwise, the leftop contains information usable
|
||||
* at runtime to figure out the value to place in our
|
||||
* scan key.
|
||||
* ----------------
|
||||
*/
|
||||
have_runtime_keys = true;
|
||||
run_keys[ j ] = RIGHT_OP;
|
||||
scanvalue = Int32GetDatum((int32) true);
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* now check that at least one op tells us the scan
|
||||
* attribute...
|
||||
* ----------------
|
||||
*/
|
||||
if (scanvar == NO_OP)
|
||||
elog(WARN, "ExecInitIndexScan: %s",
|
||||
"neither leftop nor rightop refer to scan relation");
|
||||
|
||||
/* ----------------
|
||||
* initialize the scan key's fields appropriately
|
||||
* ----------------
|
||||
*/
|
||||
ScanKeyEntryInitialize(&scan_keys[j],
|
||||
0,
|
||||
varattno, /* attribute number to scan */
|
||||
(RegProcedure) opid, /* reg proc to use */
|
||||
(Datum) scanvalue); /* constant */
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* store the key information into our array.
|
||||
* ----------------
|
||||
*/
|
||||
numScanKeys[ i ] = n_keys;
|
||||
scanKeys[ i ] = scan_keys;
|
||||
runtimeKeyInfo[ i ] = (Pointer) run_keys;
|
||||
}
|
||||
|
||||
indexstate->iss_NumIndices = numIndices;
|
||||
indexstate->iss_IndexPtr = indexPtr;
|
||||
indexstate->iss_ScanKeys = scanKeys;
|
||||
indexstate->iss_NumScanKeys = numScanKeys;
|
||||
|
||||
/* ----------------
|
||||
* If all of our keys have the form (op var const) , then we have no
|
||||
* runtime keys so we store NULL in the runtime key info.
|
||||
* Otherwise runtime key info contains an array of pointers
|
||||
* (one for each index) to arrays of flags (one for each key)
|
||||
* which indicate that the qual needs to be evaluated at runtime.
|
||||
* -cim 10/24/89
|
||||
* ----------------
|
||||
*/
|
||||
if (have_runtime_keys)
|
||||
{
|
||||
indexstate->iss_RuntimeKeyInfo = (Pointer) runtimeKeyInfo;
|
||||
}
|
||||
else {
|
||||
indexstate->iss_RuntimeKeyInfo = NULL;
|
||||
for (i=0; i < numIndices; i++) {
|
||||
List *qual;
|
||||
int n_keys;
|
||||
qual = nth(i, indxqual);
|
||||
n_keys = length(qual);
|
||||
if (n_keys > 0)
|
||||
pfree(runtimeKeyInfo[i]);
|
||||
}
|
||||
pfree(runtimeKeyInfo);
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* get the range table and direction information
|
||||
* from the execution state (these are needed to
|
||||
* open the relations).
|
||||
* ----------------
|
||||
*/
|
||||
rangeTable = estate->es_range_table;
|
||||
direction = estate->es_direction;
|
||||
|
||||
/* ----------------
|
||||
* open the base relation
|
||||
* ----------------
|
||||
*/
|
||||
relid = node->scan.scanrelid;
|
||||
rtentry = rt_fetch(relid, rangeTable);
|
||||
reloid = rtentry->relid;
|
||||
timeQual = rtentry->timeQual;
|
||||
|
||||
ExecOpenScanR(reloid, /* relation */
|
||||
0, /* nkeys */
|
||||
(ScanKey) NULL, /* scan key */
|
||||
0, /* is index */
|
||||
direction, /* scan direction */
|
||||
timeQual, /* time qual */
|
||||
¤tRelation, /* return: rel desc */
|
||||
(Pointer *) ¤tScanDesc); /* return: scan desc */
|
||||
|
||||
scanstate->css_currentRelation = currentRelation;
|
||||
scanstate->css_currentScanDesc = currentScanDesc;
|
||||
|
||||
|
||||
/* ----------------
|
||||
* get the scan type from the relation descriptor.
|
||||
* ----------------
|
||||
*/
|
||||
ExecAssignScanType(scanstate, RelationGetTupleDescriptor(currentRelation));
|
||||
ExecAssignResultTypeFromTL((Plan *) node, &scanstate->cstate);
|
||||
|
||||
/* ----------------
|
||||
* index scans don't have subtrees..
|
||||
* ----------------
|
||||
*/
|
||||
/* scanstate->ss_ProcOuterFlag = false; */
|
||||
|
||||
/* ----------------
|
||||
* open the index relations and initialize
|
||||
* relation and scan descriptors.
|
||||
* ----------------
|
||||
*/
|
||||
for (i=0; i < numIndices; i++) {
|
||||
Oid indexOid;
|
||||
|
||||
indexOid = (Oid)nth(i, indxid);
|
||||
|
||||
if (indexOid != 0) {
|
||||
ExecOpenScanR(indexOid, /* relation */
|
||||
numScanKeys[ i ], /* nkeys */
|
||||
scanKeys[ i ], /* scan key */
|
||||
true, /* is index */
|
||||
direction, /* scan direction */
|
||||
timeQual, /* time qual */
|
||||
&(relationDescs[ i ]), /* return: rel desc */
|
||||
(Pointer *) &(scanDescs[ i ]));
|
||||
/* return: scan desc */
|
||||
}
|
||||
}
|
||||
|
||||
indexstate->iss_RelationDescs = relationDescs;
|
||||
indexstate->iss_ScanDescs = scanDescs;
|
||||
|
||||
indexstate->cstate.cs_TupFromTlist = false;
|
||||
|
||||
/* ----------------
|
||||
* all done.
|
||||
* ----------------
|
||||
*/
|
||||
return TRUE;
|
||||
}
|
||||
|
||||
int
|
||||
ExecCountSlotsIndexScan(IndexScan *node)
|
||||
{
|
||||
return ExecCountSlotsNode(outerPlan((Plan *)node)) +
|
||||
ExecCountSlotsNode(innerPlan((Plan *)node)) +
|
||||
INDEXSCAN_NSLOTS;
|
||||
}
|
Reference in New Issue
Block a user