That's interesting. So if you have a composite index on two columns, is there much of a reason (usually) to create single indexes on each of the two columns? I guess the single indexes might be slightly faster depending on the number of different values/combinations, so probably "it depends" eh? On Fri, 19 Jan 2007 16:57:42 -0600, "Ron Johnson" <ron.l.johnson@xxxxxxx> said: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > On 01/19/07 15:53, Jan Muszynski wrote: > > Rather simple question, of which I'm not sure of the answer. > > > > If I have a multiple column index, say: > > Index index1 on tableA (foo,bar) > > > > and I then: > > Select * from "tableA" where foo = <some value> > > > > Will index1 be used, or am I looking at a seqscan in all circumstances? > > Yes, it will use the index. > > However, in earlier versions, the lvalue & rvalue needed to match in > type to use the index. > > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.6 (GNU/Linux) > > iD8DBQFFsUzmS9HxQb37XmcRArY8AKDqzS5FeY1HwkSGeOlhQsjsdpAV5gCghiWj > R4e7rBWaAAGF25ZFhy1Elgc= > =Wkp8 > -----END PGP SIGNATURE----- > > ---------------------------(end of broadcast)--------------------------- > TIP 1: if posting/reading through Usenet, please send an appropriate > subscribe-nomail command to majordomo@xxxxxxxxxxxxxx so that your > message can get through to the mailing list cleanly
