On Oct 12, 2010, at 8:54 AM, <david@xxxxxxx> wrote: > On Tue, 12 Oct 2010, Craig Ringer wrote: > >> On 10/12/2010 04:22 PM, david@xxxxxxx wrote: >> >>> from a PR point of view, speeding up the trivil count(*) case could be >>> worth it, just to avoid people complaining about it not being fast. >> >> At the cost of a fair bit more complexity, though, and slowing everything >> else down. > > complexity probably, although given how complex the planner is already is > this significant? > > as far as slowing everything else down, why would it do that? (beyond the > simple fact that any new thing the planner can do makes the planner take a > little longer) > > David Lang > I wouldn't even expect the planner to do more work. An Index Scan can simply avoid going to the tuples for visibility under some circumstances. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
