I don't think this will necessarily work: field1 | field2 aa | ab a | aab These are two distinct rows, so should be counted as two. The proposed method would count them as one. You can get around this problem by doing: count (distinct (a || x || b)) where x is some character not found in your data. > -----Original Message----- > From: Dirk Lutzebaeck [SMTP:[EMAIL PROTECTED]] > Sent: Wednesday, March 28, 2001 1:32 PM > To: Michael Fork > Cc: [EMAIL PROTECTED] > Subject: Re: counting distinct rows on more than one column > > Michael Fork writes: > > In 7.0.3, I believe the following would work: > > > > SELECT count(distinct(a || b)) FROM t; > > Great, this works! I don't quite get it why... > > Dirk > > ---------------------------(end of broadcast)--------------------------- > TIP 3: if posting/reading through Usenet, please send an appropriate > subscribe-nomail command to [EMAIL PROTECTED] so that your > message can get through to the mailing list cleanly ---------------------------(end of broadcast)--------------------------- TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]
