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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2005-03-27 23:53:05 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2005-03-27 23:53:05 +0000 |
| commit | bf3dbb5881e9b886ee9fe84bca2153c698eea885 (patch) | |
| tree | eaaf385364adebc2489c72f30e533f5fe60748ec /src/backend/access/heap/heapam.c | |
| parent | 351519affcffb636de68c4872521c9ac22faa228 (diff) | |
| download | postgresql-bf3dbb5881e9b886ee9fe84bca2153c698eea885.tar.gz postgresql-bf3dbb5881e9b886ee9fe84bca2153c698eea885.zip | |
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.
Diffstat (limited to 'src/backend/access/heap/heapam.c')
| -rw-r--r-- | src/backend/access/heap/heapam.c | 29 |
1 files changed, 23 insertions, 6 deletions
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)) { |