Allow GIN's extractQuery method to signal that nothing can satisfy the query.
In this case extractQuery should returns -1 as nentries. This changes prototype of extractQuery method to use int32* instead of uint32* for nentries argument. Based on that gincostestimate may see two corner cases: nothing will be found or seqscan should be used. Per proposal at http://archives.postgresql.org/pgsql-hackers/2007-01/msg01581.php PS tsearch_core patch should be sightly modified to support changes, but I'm waiting a verdict about reviewing of tsearch_core patch.
This commit is contained in:
Teodor Sigaev
parent
147a3ce149
commit
d4c6da1527
@ -6,7 +6,7 @@ Datum ginint4_queryextract(PG_FUNCTION_ARGS);
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Datum
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ginint4_queryextract(PG_FUNCTION_ARGS)
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{
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uint32 *nentries = (uint32 *) PG_GETARG_POINTER(1);
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int32 *nentries = (int32 *) PG_GETARG_POINTER(1);
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StrategyNumber strategy = PG_GETARG_UINT16(2);
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Datum *res = NULL;
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@ -57,6 +57,19 @@ ginint4_queryextract(PG_FUNCTION_ARGS)
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}
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}
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if ( nentries == 0 )
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{
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switch( strategy )
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{
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case BooleanSearchStrategy:
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case RTOverlapStrategyNumber:
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*nentries = -1; /* nobody can be found */
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break;
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default: /* require fullscan: GIN can't find void arrays */
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break;
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}
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}
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PG_RETURN_POINTER(res);
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}
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@ -21,7 +21,7 @@ Datum
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gin_extract_tsvector(PG_FUNCTION_ARGS)
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{
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tsvector *vector = (tsvector *) PG_DETOAST_DATUM(PG_GETARG_DATUM(0));
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uint32 *nentries = (uint32 *) PG_GETARG_POINTER(1);
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int32 *nentries = (int32 *) PG_GETARG_POINTER(1);
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Datum *entries = NULL;
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*nentries = 0;
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@ -30,7 +30,7 @@ gin_extract_tsvector(PG_FUNCTION_ARGS)
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int i;
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WordEntry *we = ARRPTR(vector);
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*nentries = (uint32) vector->size;
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*nentries = (int32) vector->size;
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entries = (Datum *) palloc(sizeof(Datum) * vector->size);
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for (i = 0; i < vector->size; i++)
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@ -58,7 +58,7 @@ Datum
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gin_extract_tsquery(PG_FUNCTION_ARGS)
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{
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QUERYTYPE *query = (QUERYTYPE *) PG_DETOAST_DATUM(PG_GETARG_DATUM(0));
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uint32 *nentries = (uint32 *) PG_GETARG_POINTER(1);
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int32 *nentries = (int32 *) PG_GETARG_POINTER(1);
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StrategyNumber strategy = DatumGetUInt16(PG_GETARG_DATUM(2));
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Datum *entries = NULL;
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@ -99,6 +99,8 @@ gin_extract_tsquery(PG_FUNCTION_ARGS)
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}
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}
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else
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*nentries = -1; /* nothing can be found */
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PG_FREE_IF_COPY(query, 0);
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PG_RETURN_POINTER(entries);
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@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/gin.sgml,v 2.7 2006/12/01 23:46:46 tgl Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/gin.sgml,v 2.8 2007/01/31 15:09:45 teodor Exp $ -->
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<chapter id="GIN">
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<title>GIN Indexes</title>
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@ -77,7 +77,7 @@
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</varlistentry>
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<varlistentry>
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<term>Datum* extractValue(Datum inputValue, uint32 *nkeys)</term>
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<term>Datum* extractValue(Datum inputValue, int32 *nkeys)</term>
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<listitem>
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<para>
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Returns an array of keys given a value to be indexed. The
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@ -87,7 +87,7 @@
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</varlistentry>
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<varlistentry>
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<term>Datum* extractQuery(Datum query, uint32 *nkeys,
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<term>Datum* extractQuery(Datum query, int32 *nkeys,
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StrategyNumber n)</term>
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<listitem>
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<para>
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@ -100,6 +100,12 @@
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to consult <literal>n</> to determine the data type of
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<literal>query</> and the key values that need to be extracted.
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The number of returned keys must be stored into <literal>*nkeys</>.
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If number of keys is equal to zero then <function>extractQuery</>
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should store 0 or -1 into <literal>*nkeys</>. 0 means that any
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row matches the <literal>query</> and sequence scan should be
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produced. -1 means nothing can satisfy <literal>query</>.
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Choice of value should be based on semantics meaning of operation with
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given strategy number.
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</para>
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</listitem>
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</varlistentry>
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@ -8,7 +8,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/access/gin/ginarrayproc.c,v 1.8 2007/01/05 22:19:21 momjian Exp $
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* $PostgreSQL: pgsql/src/backend/access/gin/ginarrayproc.c,v 1.9 2007/01/31 15:09:45 teodor Exp $
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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@ -38,7 +38,7 @@ Datum
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ginarrayextract(PG_FUNCTION_ARGS)
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{
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ArrayType *array;
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uint32 *nentries = (uint32 *) PG_GETARG_POINTER(1);
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int32 *nentries = (int32 *) PG_GETARG_POINTER(1);
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Datum *entries = NULL;
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int16 elmlen;
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bool elmbyval;
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@ -60,6 +60,21 @@ ginarrayextract(PG_FUNCTION_ARGS)
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elmlen, elmbyval, elmalign,
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&entries, NULL, (int *) nentries);
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if ( *nentries == 0 && PG_NARGS() == 3 )
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{
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switch( PG_GETARG_UINT16(2) )
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{
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case GinOverlapStrategy:
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*nentries = -1; /* nobody can be found */
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break;
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case GinContainsStrategy:
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case GinContainedStrategy:
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case GinEqualStrategy:
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default: /* require fullscan: GIN can't find void arrays */
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break;
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}
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}
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/* we should not free array, entries[i] points into it */
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PG_RETURN_POINTER(entries);
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}
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@ -8,7 +8,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/access/gin/ginbulk.c,v 1.7 2007/01/05 22:19:21 momjian Exp $
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* $PostgreSQL: pgsql/src/backend/access/gin/ginbulk.c,v 1.8 2007/01/31 15:09:45 teodor Exp $
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*-------------------------------------------------------------------------
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*/
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@ -191,13 +191,13 @@ ginChooseElem(BuildAccumulator *accum, ItemPointer heapptr, Datum *entries, uint
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* next middle on left part and middle of right part.
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*/
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void
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ginInsertRecordBA(BuildAccumulator *accum, ItemPointer heapptr, Datum *entries, uint32 nentry)
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ginInsertRecordBA(BuildAccumulator *accum, ItemPointer heapptr, Datum *entries, int32 nentry)
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{
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uint32 i,
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nbit = 0,
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offset;
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if (nentry == 0)
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if (nentry <= 0)
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return;
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i = nentry - 1;
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@ -8,7 +8,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/access/gin/ginget.c,v 1.5 2007/01/05 22:19:21 momjian Exp $
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* $PostgreSQL: pgsql/src/backend/access/gin/ginget.c,v 1.6 2007/01/31 15:09:45 teodor Exp $
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*-------------------------------------------------------------------------
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*/
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@ -420,6 +420,7 @@ scanGetItem(IndexScanDesc scan, ItemPointerData *item)
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}
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#define GinIsNewKey(s) ( ((GinScanOpaque) scan->opaque)->keys == NULL )
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#define GinIsVoidRes(s) ( ((GinScanOpaque) scan->opaque)->isVoidRes == true )
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Datum
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gingetmulti(PG_FUNCTION_ARGS)
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@ -432,10 +433,13 @@ gingetmulti(PG_FUNCTION_ARGS)
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if (GinIsNewKey(scan))
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newScanKey(scan);
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startScan(scan);
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*returned_tids = 0;
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if (GinIsVoidRes(scan))
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PG_RETURN_BOOL(false);
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startScan(scan);
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do
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{
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if (scanGetItem(scan, tids + *returned_tids))
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@ -462,6 +466,9 @@ gingettuple(PG_FUNCTION_ARGS)
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if (GinIsNewKey(scan))
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newScanKey(scan);
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if (GinIsVoidRes(scan))
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PG_RETURN_BOOL(false);
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startScan(scan);
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res = scanGetItem(scan, &scan->xs_ctup.t_self);
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stopScan(scan);
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@ -8,7 +8,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/access/gin/gininsert.c,v 1.6 2007/01/05 22:19:21 momjian Exp $
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* $PostgreSQL: pgsql/src/backend/access/gin/gininsert.c,v 1.7 2007/01/31 15:09:45 teodor Exp $
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*-------------------------------------------------------------------------
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*/
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@ -203,7 +203,7 @@ static uint32
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ginHeapTupleBulkInsert(GinBuildState *buildstate, Datum value, ItemPointer heapptr)
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{
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Datum *entries;
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uint32 nentries;
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int32 nentries;
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MemoryContext oldCtx;
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oldCtx = MemoryContextSwitchTo(buildstate->funcCtx);
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@ -356,7 +356,7 @@ static uint32
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ginHeapTupleInsert(Relation index, GinState *ginstate, Datum value, ItemPointer item)
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{
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Datum *entries;
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uint32 i,
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int32 i,
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nentries;
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entries = extractEntriesSU(ginstate, value, &nentries);
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@ -8,7 +8,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/access/gin/ginscan.c,v 1.8 2007/01/05 22:19:21 momjian Exp $
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* $PostgreSQL: pgsql/src/backend/access/gin/ginscan.c,v 1.9 2007/01/31 15:09:45 teodor Exp $
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*-------------------------------------------------------------------------
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*/
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@ -145,10 +145,12 @@ newScanKey(IndexScanDesc scan)
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(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
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errmsg("GIN indexes do not support whole-index scans")));
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so->isVoidRes = false;
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for (i = 0; i < scan->numberOfKeys; i++)
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{
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Datum *entryValues;
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uint32 nEntryValues;
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int32 nEntryValues;
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if (scankey[i].sk_flags & SK_ISNULL)
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elog(ERROR, "Gin doesn't support NULL as scan key");
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@ -162,6 +164,15 @@ newScanKey(IndexScanDesc scan)
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UInt16GetDatum(scankey[i].sk_strategy)
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)
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);
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if ( nEntryValues < 0 )
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{
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/*
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* extractQueryFn signals that nothing will be found,
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* so we can just set isVoidRes flag...
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*/
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so->isVoidRes = true;
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break;
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}
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if (entryValues == NULL || nEntryValues == 0)
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/* full scan... */
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continue;
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@ -173,7 +184,7 @@ newScanKey(IndexScanDesc scan)
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so->nkeys = nkeys;
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if (so->nkeys == 0)
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if (so->nkeys == 0 && !so->isVoidRes)
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ereport(ERROR,
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(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
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errmsg("GIN index does not support search with void query")));
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@ -8,7 +8,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/access/gin/ginutil.c,v 1.9 2007/01/05 22:19:21 momjian Exp $
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* $PostgreSQL: pgsql/src/backend/access/gin/ginutil.c,v 1.10 2007/01/31 15:09:45 teodor Exp $
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*-------------------------------------------------------------------------
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*/
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@ -148,7 +148,7 @@ cmpEntries(const Datum *a, const Datum *b, cmpEntriesData *arg)
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}
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Datum *
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extractEntriesS(GinState *ginstate, Datum value, uint32 *nentries,
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extractEntriesS(GinState *ginstate, Datum value, int32 *nentries,
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bool *needUnique)
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{
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Datum *entries;
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@ -178,7 +178,7 @@ extractEntriesS(GinState *ginstate, Datum value, uint32 *nentries,
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Datum *
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extractEntriesSU(GinState *ginstate, Datum value, uint32 *nentries)
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extractEntriesSU(GinState *ginstate, Datum value, int32 *nentries)
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{
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bool needUnique;
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Datum *entries = extractEntriesS(ginstate, value, nentries,
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@ -15,7 +15,7 @@
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*
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.223 2007/01/28 02:53:34 tgl Exp $
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* $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.224 2007/01/31 15:09:45 teodor Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -76,6 +76,7 @@
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#include <ctype.h>
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#include <math.h>
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#include "access/gin.h"
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#include "catalog/pg_opfamily.h"
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#include "catalog/pg_statistic.h"
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#include "catalog/pg_type.h"
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@ -5286,7 +5287,120 @@ gincostestimate(PG_FUNCTION_ARGS)
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Cost *indexTotalCost = (Cost *) PG_GETARG_POINTER(5);
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Selectivity *indexSelectivity = (Selectivity *) PG_GETARG_POINTER(6);
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double *indexCorrelation = (double *) PG_GETARG_POINTER(7);
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ListCell *l;
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int32 nfullscan = 0;
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/*
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* GIN doesn't support full index scan.
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* If quals require full index scan then we should
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* return cost big as possible to forbid full index scan.
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*/
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foreach(l, indexQuals)
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{
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RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
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Expr *clause;
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Node *leftop,
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*rightop,
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*operand;
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Oid extractProcOid;
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Oid clause_op;
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int strategy_op;
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Oid lefttype,
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righttype;
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bool recheck;
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int32 nentries;
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/*
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* For each clause it's needed to check operand
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* for values to search in GIN. So, we should find
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* extractQuery method to get values from operand
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*/
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Assert(IsA(rinfo, RestrictInfo));
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clause = rinfo->clause;
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Assert( IsA(clause, OpExpr) );
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leftop = get_leftop(clause);
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rightop = get_rightop(clause);
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clause_op = ((OpExpr *) clause)->opno;
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if (match_index_to_operand(leftop, 0 /* GiN has only one column */, index))
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{
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operand = rightop;
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}
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else if (match_index_to_operand(rightop, 0, index))
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{
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operand = leftop;
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clause_op = get_commutator(clause_op);
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}
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if ( IsA(operand, RelabelType) )
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operand = (Node *) ((RelabelType *) operand)->arg;
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/*
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* It's impossible to call extractQuery method for not yet
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* known operand (taken from table, for example). In this
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* case we can't do anything useful...
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*/
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if ( !IsA(operand, Const) )
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continue;
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if (!op_in_opfamily(clause_op, index->opfamily[0]))
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continue;
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/*
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* lefttype is a type of index column, righttype is a
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* type of operand (query)
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*/
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get_op_opfamily_properties( clause_op, index->opfamily[0],
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&strategy_op, &lefttype, &righttype, &recheck);
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/*
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* GIN (as GiST) always has lefttype == righttype in pg_amproc
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* and they are equal to type Oid on which index was created/designed
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*/
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extractProcOid = get_opfamily_proc( index->opfamily[0],
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lefttype, lefttype,
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GIN_EXTRACTQUERY_PROC );
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if ( !OidIsValid(extractProcOid) )
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continue; /* should not be */
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OidFunctionCall3( extractProcOid,
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((Const*)operand)->constvalue,
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PointerGetDatum(&nentries),
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UInt16GetDatum(strategy_op));
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if ( nentries == 0 )
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nfullscan++;
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else if ( nentries < 0 )
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{
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/*
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* GIN_EXTRACTQUERY_PROC guarantees that nothing will be found
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*/
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*indexStartupCost = 0;
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*indexTotalCost = 0;
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*indexSelectivity = 0;
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*indexCorrelation = 0;
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PG_RETURN_VOID();
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}
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}
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if ( nfullscan == list_length(indexQuals) )
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{
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/*
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* All quals are void and require full scan. So
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* set max possible cost to prevent index scan.
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*/
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*indexStartupCost = disable_cost;
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*indexTotalCost = disable_cost;
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*indexSelectivity = 1.0;
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*indexCorrelation = 0;
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PG_RETURN_VOID();
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}
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||||
|
||||
|
||||
genericcostestimate(root, index, indexQuals, outer_rel, 0.0,
|
||||
indexStartupCost, indexTotalCost,
|
||||
indexSelectivity, indexCorrelation);
|
||||
|
||||
@ -3,7 +3,7 @@
|
||||
* header file for postgres inverted index access method implementation.
|
||||
*
|
||||
* Copyright (c) 2006, PostgreSQL Global Development Group
|
||||
* $PostgreSQL: pgsql/src/include/access/gin.h,v 1.9 2006/10/05 17:57:40 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/include/access/gin.h,v 1.10 2007/01/31 15:09:45 teodor Exp $
|
||||
*--------------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
@ -233,8 +233,8 @@ extern void GinInitBuffer(Buffer b, uint32 f);
|
||||
extern void GinInitPage(Page page, uint32 f, Size pageSize);
|
||||
extern int compareEntries(GinState *ginstate, Datum a, Datum b);
|
||||
extern Datum *extractEntriesS(GinState *ginstate, Datum value,
|
||||
uint32 *nentries, bool *needUnique);
|
||||
extern Datum *extractEntriesSU(GinState *ginstate, Datum value, uint32 *nentries);
|
||||
int32 *nentries, bool *needUnique);
|
||||
extern Datum *extractEntriesSU(GinState *ginstate, Datum value, int32 *nentries);
|
||||
extern Page GinPageGetCopyPage(Page page);
|
||||
|
||||
/* gininsert.c */
|
||||
@ -399,6 +399,8 @@ typedef struct GinScanOpaqueData
|
||||
|
||||
GinScanKey keys;
|
||||
uint32 nkeys;
|
||||
bool isVoidRes; /* true if ginstate.extractQueryFn
|
||||
guarantees that nothing will be found */
|
||||
|
||||
GinScanKey markPos;
|
||||
} GinScanOpaqueData;
|
||||
@ -458,7 +460,7 @@ typedef struct
|
||||
|
||||
extern void ginInitBA(BuildAccumulator *accum);
|
||||
extern void ginInsertRecordBA(BuildAccumulator *accum,
|
||||
ItemPointer heapptr, Datum *entries, uint32 nentry);
|
||||
ItemPointer heapptr, Datum *entries, int32 nentry);
|
||||
extern ItemPointerData *ginGetEntry(BuildAccumulator *accum, Datum *entry, uint32 *n);
|
||||
|
||||
#endif
|
||||
|
||||
Loading…
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Reference in New Issue
Block a user