When grilled further on (Mon, 12 Jan 2004 07:28:09 +0100), Tomasz Myrta <[EMAIL PROTECTED]> confessed:
> Dnia 2004-01-12 05:04, Użytkownik Robert Creager napisał: > > > > SELECT date_trunc( 'hour', "when" )::timestamp AS > > period FROM readings WHERE period NOT IN (SELECT "time" FROM > > hour.summary_period) GROUP BY period ORDER BY period; > > > > The error is: > > > > ERROR: column "period" does not exist > > > Your problem has nothing to "NOT IN". > Your query works fine, when you remove column alias from WHERE clause - > it's beacause WHERE clause is executed *before* data output (and before > column aliases). You can still use column aliases in "GROUP BY" and > "ORDER BY". Thanks for the info. So now I have: SELECT p.period FROM (SELECT date_trunc( 'hour', "when" )::timestamp AS period FROM readings GROUP BY period) AS p WHERE p.period NOT IN (SELECT "time" FROM hour.summary_period) ORDER BY p.period; which appears works as expected. Anything obviously goofy with the above query? Cheers, Rob -- 05:57:10 up 14 days, 19:47, 4 users, load average: 2.17, 2.07, 2.04
pgp00000.pgp
Description: PGP signature