On 9/11/07, Bruce Momjian <[EMAIL PROTECTED]> wrote: > > > > Right. My point is that pruning only modifies item pointers. It does > not change the actual heap tuples. In the quote above, how is Heikki's > "quick pruning" different from the pruning you are describing? > > > I think the only difference is that the quick pruning does not mark intermediate tuples ~LP_USED and hence we may avoid WAL logging.
Btw, I am not too enthusiastic about quick pruning because it leaves behind dead heap-only tuples which are not reachable from any root heap tuples. Not that we can't handle them, but I am worried about making such changes right now unless we are sure about the benefits. We can always tune and tweak in 8.4 Thanks, Pavan -- Pavan Deolasee EnterpriseDB http://www.enterprisedb.com