On Thu, Oct 19, 2006 at 06:19:16PM +0100, Richard Huxton wrote: > OK - these plans look about the same, but the time is greatly different. > Both have rows=140247 as the estimated number of rows in tbl_reg. Either > you have many more rows in the second case (in which case you're not > running ANALYSE enough) or you have lots of gaps in the table (you're > not running VACUUM enough). Look closer... the actual stats show that the sorts in the second case are returning far more rows. And yes, analyze probably needs to happen. > I'd then try putting an index on (attr1,attr2,attr3...attr6) and see if > that helps reduce time. With bitmap index scans, I think it'd be much better to create 6 indexes and see which ones actually get used (and then drop the others). -- Jim Nasby jim@xxxxxxxxx EnterpriseDB http://enterprisedb.com 512.569.9461 (cell)
