Update comment for _bt_relandgetbuf.

This commit is contained in:
Tom Lane 2009-05-05 19:02:22 +00:00
parent 40bc4c2605
commit 2aa5ca952f

View File

@ -9,7 +9,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtpage.c,v 1.112 2009/01/01 17:23:35 momjian Exp $
* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtpage.c,v 1.113 2009/05/05 19:02:22 tgl Exp $
*
* NOTES
* Postgres btree pages look like ordinary relation pages. The opaque
@ -569,8 +569,12 @@ _bt_getbuf(Relation rel, BlockNumber blkno, int access)
* This is equivalent to _bt_relbuf followed by _bt_getbuf, with the
* exception that blkno may not be P_NEW. Also, if obuf is InvalidBuffer
* then it reduces to just _bt_getbuf; allowing this case simplifies some
* callers. The motivation for using this is to avoid two entries to the
* bufmgr when one will do.
* callers.
*
* The original motivation for using this was to avoid two entries to the
* bufmgr when one would do. However, now it's mainly just a notational
* convenience. The only case where it saves work over _bt_relbuf/_bt_getbuf
* is when the target page is the same one already in the buffer.
*/
Buffer
_bt_relandgetbuf(Relation rel, Buffer obuf, BlockNumber blkno, int access)