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34235a295b
so that the fmgr lookup only has to happen once per index scan and not once per tuple. Seems to save 5% or so of CPU time for an indexscan.
83 lines
2.6 KiB
C
83 lines
2.6 KiB
C
/*-------------------------------------------------------------------------
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*
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* relscan.h
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* POSTGRES internal relation scan descriptor definitions.
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*
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*
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* Portions Copyright (c) 1996-2000, PostgreSQL, Inc
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $Id: relscan.h,v 1.19 2000/03/14 23:52:00 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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#ifndef RELSCAN_H
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#define RELSCAN_H
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#include "utils/tqual.h"
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typedef ItemPointerData MarkData;
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typedef struct HeapScanDescData
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{
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Relation rs_rd; /* pointer to relation descriptor */
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HeapTupleData rs_ptup; /* previous tuple in scan */
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HeapTupleData rs_ctup; /* current tuple in scan */
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HeapTupleData rs_ntup; /* next tuple in scan */
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Buffer rs_pbuf; /* previous buffer in scan */
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Buffer rs_cbuf; /* current buffer in scan */
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Buffer rs_nbuf; /* next buffer in scan */
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ItemPointerData rs_mptid; /* marked previous tid */
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ItemPointerData rs_mctid; /* marked current tid */
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ItemPointerData rs_mntid; /* marked next tid */
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ItemPointerData rs_mcd; /* marked current delta XXX ??? */
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Snapshot rs_snapshot; /* snapshot to see */
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bool rs_atend; /* restart scan at end? */
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uint16 rs_cdelta; /* current delta in chain */
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uint16 rs_nkeys; /* number of attributes in keys */
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ScanKey rs_key; /* key descriptors */
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} HeapScanDescData;
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typedef HeapScanDescData *HeapScanDesc;
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typedef struct IndexScanDescData
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{
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Relation relation; /* relation descriptor */
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void *opaque; /* am-specific slot */
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ItemPointerData previousItemData; /* previous index pointer */
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ItemPointerData currentItemData; /* current index pointer */
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ItemPointerData nextItemData; /* next index pointer */
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MarkData previousMarkData; /* marked previous pointer */
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MarkData currentMarkData;/* marked current pointer */
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MarkData nextMarkData; /* marked next pointer */
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uint8 flags; /* scan position flags */
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bool scanFromEnd; /* restart scan at end? */
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uint16 numberOfKeys; /* number of key attributes */
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ScanKey keyData; /* key descriptor */
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FmgrInfo fn_getnext; /* cached lookup info for am's getnext fn */
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} IndexScanDescData;
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typedef IndexScanDescData *IndexScanDesc;
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/* ----------------
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* IndexScanDescPtr is used in the executor where we have to
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* keep track of several index scans when using several indices
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* - cim 9/10/89
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* ----------------
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*/
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typedef IndexScanDesc *IndexScanDescPtr;
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/*
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* HeapScanIsValid
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* True iff the heap scan is valid.
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*/
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#define HeapScanIsValid(scan) PointerIsValid(scan)
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/*
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* IndexScanIsValid
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* True iff the index scan is valid.
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*/
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#define IndexScanIsValid(scan) PointerIsValid(scan)
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#endif /* RELSCAN_H */
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