"Tom Lane" <[EMAIL PROTECTED]> writes: > Gregory Stark <[EMAIL PROTECTED]> writes: >> "Tom Lane" <[EMAIL PROTECTED]> writes: >>> I don't understand which part of "we can do that now" isn't clear to you. > >> Uh, except we can't. > > I already demonstrated that we could. If the problem is that the > planner is cutting over from one plan type to the other at the wrong > rowcount because of bad cost estimates, that's a different issue > altogether.
We seem to be talking past each other. The plan you showed is analogous but using a plain old index scan. That means it has to look up each matching record in a separate index scan, potentially repeatedly. A bitmap index scan would be able to look up precisely the elements in the hash in sequential order and precisely once. -- Gregory Stark EnterpriseDB http://www.enterprisedb.com Get trained by Bruce Momjian - ask me about EnterpriseDB's PostgreSQL training! -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
