database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-09-03 15:22:11 +03:00
Code Activity

Replace "amgetmulti" AM functions with "amgetbitmap", in which the whole

Browse Source 
indexscan always occurs in one call, and the results are returned in a
TIDBitmap instead of a limited-size array of TIDs.  This should improve
speed a little by reducing AM entry/exit overhead, and it is necessary
infrastructure if we are ever to support bitmap indexes.

In an only slightly related change, add support for TIDBitmaps to preserve
(somewhat lossily) the knowledge that particular TIDs reported by an index
need to have their quals rechecked when the heap is visited.  This facility
is not really used yet; we'll need to extend the forced-recheck feature to
plain indexscans before it's useful, and that hasn't been coded yet.
The intent is to use it to clean up 8.3's horrid @@@ kluge for text search
with weighted queries.  There might be other uses in future, but that one
alone is sufficient reason.

Heikki Linnakangas, with some adjustments by me.
This commit is contained in:
Tom Lane
2008-04-10 22:25:26 +00:00
parent f260edb144
commit 4e82a95476
30 changed files with 420 additions and 269 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
src/include/access/genam.h
View File

@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/genam.h,v 1.69 2008/01/01 19:45:56 momjian Exp $
* $PostgreSQL: pgsql/src/include/access/genam.h,v 1.70 2008/04/10 22:25:25 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -17,6 +17,7 @@
#include "access/relscan.h"
#include "access/sdir.h"
#include "nodes/primnodes.h"
#include "nodes/tidbitmap.h"
#include "storage/lock.h"
/*
@@ -99,7 +100,7 @@ extern IndexScanDesc index_beginscan(Relation heapRelation,
Relation indexRelation,
Snapshot snapshot,
int nkeys, ScanKey key);
extern IndexScanDesc index_beginscan_multi(Relation indexRelation,
extern IndexScanDesc index_beginscan_bitmap(Relation indexRelation,
Snapshot snapshot,
int nkeys, ScanKey key);
extern void index_rescan(IndexScanDesc scan, ScanKey key);
@@ -109,9 +110,7 @@ extern void index_restrpos(IndexScanDesc scan);
extern HeapTuple index_getnext(IndexScanDesc scan, ScanDirection direction);
extern bool index_getnext_indexitem(IndexScanDesc scan,
ScanDirection direction);
extern bool index_getmulti(IndexScanDesc scan,
ItemPointer tids, int32 max_tids,
int32 *returned_tids);
extern int64 index_getbitmap(IndexScanDesc scan, TIDBitmap *bitmap);
extern IndexBulkDeleteResult *index_bulk_delete(IndexVacuumInfo *info,
IndexBulkDeleteResult *stats,