When grilled further on (Mon, 9 Jan 2006 22:58:18 -0700), Michael Fuhr <mike@xxxxxxxx> confessed: > On Mon, Jan 09, 2006 at 09:23:38PM -0700, Robert Creager wrote: > > I'm working with a query to get more info out with a join. The base > > query works great speed wise because of index usage. When the join is > > tossed in, the index is no longer used, so the query performance tanks. > > The first query you posted returns 285 rows and the second returns > over one million; index usage aside, that difference surely accounts > for a performance penalty. And as is often pointed out, index scans > aren't always faster than sequential scans: the more of a table a > query has to fetch, the more likely a sequential scan will be faster. Thanks for pointing out the obvious that I missed. Too much data in the second query. It's supposed to match (row wise) what was returned from the first query. Just ignore me for now... Thanks, Rob -- 08:15:24 up 3 days, 42 min, 9 users, load average: 2.07, 2.20, 2.25 Linux 2.6.12-12-2 #4 SMP Tue Jan 3 19:56:19 MST 2006
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