Christoph Pingel <ch.pingel@xxxxxx> writes: > Am 08.08.2006 um 19:49 schrieb Nikolay Samokhvalov: >> don't use "DISTINCT ON" at all, it's evil :-) (why? >> http://chernowiki.ru/index.php?node=38#A13 > Thanks for the good advice! From reading this, it seems to be a > *really* bad thing. And I didn't get it from the official > documentation. :-) That page is complaining about DISTINCT ON as it was defined in 1999. It's a lot harder to shoot yourself in the foot now: regression=# select distinct on (ten) hundred from tenk1 order by unique2; ERROR: SELECT DISTINCT ON expressions must match initial ORDER BY expressions I don't deny that it's nonstandard and pretty ugly, but sometimes it's just really hard to solve a problem any other way. regards, tom lane
