Martijn van Oosterhout wrote: -- Start of PGP signed section. > On Mon, Jun 26, 2006 at 07:17:31AM -0400, Bruce Momjian wrote: > > Correct! We use the same pointers used by normal UPDATEs, except we set > > a bit on the old tuple indicating it is a single-index tuple, and we > > don't create index entries for the new tuple. Index scan routines will > > need to be taught about the new chains, but because only one tuple in > > the chain is visible to a single backend, the callers should not need to > > be modified. > > I suppose we would also change the index_getmulti() function to return > a set of ctids plus flags so the caller knows to follow the chains, > right? And for bitmap index scans you would only remember the page in > the case of such a tuple, since you can't be sure the exact ctid you've > got is the one you want. > > Seems doable.
Yes, it just is an issue of where you want to add the complexity --- scan entire page when no free space, or only an UPDATE. -- Bruce Momjian [EMAIL PROTECTED] EnterpriseDB http://www.enterprisedb.com + If your life is a hard drive, Christ can be your backup. + ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
