15.02.2014 13:25, liviusliv...@poczta.onet.pl wrote: > > Your explanation is very good but i see that i was not clear in question. > I understand that collate is for sorting or upper but what is difference > in maining of collation in this three queries. > What do > Select field collate pxw_plk from ... > > What do > .... Group by field collate pxw_plk > > What difference if i remove collate?
Think about COLLATE as about CAST. Collation overrides default comparison rules, so "field" and "field collate pxw_plk" may lead to a different grouping (imagine a case-insensitive collation for example). As GROUP BY requires that the select list and group list must be exactly the same expressions, you get the error. Dmitry ------------------------------------------------------------------------------ Android apps run on BlackBerry 10 Introducing the new BlackBerry 10.2.1 Runtime for Android apps. Now with support for Jelly Bean, Bluetooth, Mapview and more. Get your Android app in front of a whole new audience. Start now. http://pubads.g.doubleclick.net/gampad/clk?id=124407151&iu=/4140/ostg.clktrk Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel
