O CHRIS HOOVER έγραψε στις Oct 8, 2004 :
> Just curious, what is wrong with the first way of coding the solution? > ------------------( Forwarded letter 1 follows )--------------------- > Date: Fri, 8 Oct 2004 08:44:23 +0400 > To: Thomas.F.O'[EMAIL PROTECTED], [EMAIL PROTECTED] > Cc: [EMAIL PROTECTED] > From: [EMAIL PROTECTED] > Sender: [EMAIL PROTECTED] > Subject: Re: [SQL] help on a query > > On Friday 08 October 2004 07:10, Thomas F.O'Connell wrote: > > A query that should get the job done is: > > > > SELECT registration_id > > FROM registrations r > > WHERE NOT EXISTS ( > > SELECT 1 > > FROM receipts > > WHERE registration_id = r.registration_id > > ); > > Don't, PLEASE, don't !!! > > drive this way : > > SELECT r.registration_id > FROM registrations AS r > LEFT OUTER JOIN receipts AS rec > ON rec.registration_id = r.registration_id > WHERE rec.registration_id IS NULL; Some one could add the same dont please dont, and advise: select registration_id FROM registrations where registration_id not in (select registration_id from receipts); but its actually version/data dependent i suppose. > > > > ---------------------------(end of broadcast)--------------------------- > TIP 6: Have you searched our list archives? > > http://archives.postgresql.org > > ---------------------------(end of broadcast)--------------------------- > TIP 6: Have you searched our list archives? > > http://archives.postgresql.org > -- -Achilleus ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html
