On Thu, Jun 08, 2006 at 03:20:55PM -0400, Tom Lane wrote: > "Andrus" <[EMAIL PROTECTED]> writes: > > Why Postgres 8.1 does not use makse_kuupaev_idx index in the following > > query > > ? > > Because it doesn't help --- the system still has to do the sort. > You'd need a two-column index on both of the ORDER BY columns to avoid > sorting.
And even then you better have a pretty high correlation on the first column, otherwise you'll still get a seqscan. -- Jim C. Nasby, Sr. Engineering Consultant [EMAIL PROTECTED] Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461 ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org
