On 8/18/06, John Siracusa <[EMAIL PROTECTED]> wrote: > ...where "extension of the standard" here means "crazy thing that > makes no sense." > > CREATE TABLE t (a INT, b INT, c INT); > > INSERT INTO t VALUES (1, 2, 3); > INSERT INTO t VALUES (1, 2, 4); > INSERT INTO t VALUES (1, 2, 5); > INSERT INTO t VALUES (1, 2, 6); > > Now guess what value c will have in the row returned by this query: > > SELECT a, SUM(b), c FROM t GROUP BY a; > > Good old MySQL...
Sure, the columns you select must have unique values per group. That limitation used to be stated in the MySQL docs. It may still be, but I can't find it now. Within that limitation, the extension can be handy in some circumstances, but as with any non-standard feature, you're increasing the pain you'll feel if you migrate to another DB in the future. _______________________________________________ List: http://lists.rawmode.org/cgi-bin/mailman/listinfo/dbix-class Wiki: http://dbix-class.shadowcatsystems.co.uk/ IRC: irc.perl.org#dbix-class SVN: http://dev.catalyst.perl.org/repos/bast/trunk/DBIx-Class/ Searchable Archive: http://www.mail-archive.com/[email protected]/
