From bf3dbb5881e9b886ee9fe84bca2153c698eea885 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sun, 27 Mar 2005 23:53:05 +0000 Subject: First steps towards index scans with heap access decoupled from index access: define new index access method functions 'amgetmulti' that can fetch multiple TIDs per call. (The functions exist but are totally untested as yet.) Since I was modifying pg_am anyway, remove the no-longer-needed 'rel' parameter from amcostestimate functions, and also remove the vestigial amowner column that was creating useless work for Alvaro's shared-object-dependencies project. Initdb forced due to changes in pg_am. --- src/backend/access/heap/heapam.c | 29 +++++++++++++++++++++++------ 1 file changed, 23 insertions(+), 6 deletions(-) (limited to 'src/backend/access/heap/heapam.c') diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c index 4b540c857b7..b5020863000 100644 --- a/src/backend/access/heap/heapam.c +++ b/src/backend/access/heap/heapam.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.184 2005/03/20 23:40:23 neilc Exp $ + * $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.185 2005/03/27 23:52:58 tgl Exp $ * * * INTERFACE ROUTINES @@ -933,18 +933,35 @@ heap_release_fetch(Relation relation, * Need share lock on buffer to examine tuple commit status. */ LockBuffer(buffer, BUFFER_LOCK_SHARE); + dp = (PageHeader) BufferGetPage(buffer); /* - * get the item line pointer corresponding to the requested tid + * We'd better check for out-of-range offnum in case of VACUUM since + * the TID was obtained. */ - dp = (PageHeader) BufferGetPage(buffer); offnum = ItemPointerGetOffsetNumber(tid); + if (offnum < FirstOffsetNumber || offnum > PageGetMaxOffsetNumber(dp)) + { + LockBuffer(buffer, BUFFER_LOCK_UNLOCK); + if (keep_buf) + *userbuf = buffer; + else + { + ReleaseBuffer(buffer); + *userbuf = InvalidBuffer; + } + tuple->t_datamcxt = NULL; + tuple->t_data = NULL; + return false; + } + + /* + * get the item line pointer corresponding to the requested tid + */ lp = PageGetItemId(dp, offnum); /* - * must check for deleted tuple (see for example analyze.c, which is - * careful to pass an offnum in range, but doesn't know if the offnum - * actually corresponds to an undeleted tuple). + * Must check for deleted tuple. */ if (!ItemIdIsUsed(lp)) { -- cgit v1.2.3