Alvaro Herrera wrote: > Jan Wieck wrote: > > On 6/25/2006 10:12 PM, Bruce Momjian wrote: > > >When you are using the update chaining, you can't mark that index row as > > >dead because it actually points to more than one row on the page, some > > >are non-visible, some are visible. > > > > Back up the truck ... you mean in the current code base we have heap > > tuples that are visible in index scans because of heap tuple chaining > > but without index tuples pointing directly at them? > > I don't know where this idea came from, but it's not true. All heap > tuples, dead or otherwise, have index entries. Unless the idea is to > extend update chaining to mean something different from the current > meaning.
It does mean something different. Single-Index-Tuple Chain (CITC) is a special type of update chaining where the updates are all on the same row, and a single index entry points to the entire chain. -- 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 4: Have you searched our list archives? http://archives.postgresql.org
