Re: sub-limiting a query
От | A. Kretschmer |
---|---|
Тема | Re: sub-limiting a query |
Дата | |
Msg-id | 20070217150033.GA30177@a-kretschmer.de обсуждение исходный текст |
Ответ на | sub-limiting a query (Louis-David Mitterrand <vindex+lists-pgsql-sql@apartia.org>) |
Список | pgsql-sql |
am Sat, dem 17.02.2007, um 13:56:35 +0100 mailte Louis-David Mitterrand folgendes: > Hello, > > I've got a table of shows with different types (movie, theater, > ballet,etc.) and I am looking for a select that can return the 10 last > entered shows AND at most 2 of each type. Is that possible in one query? > > The table looks basically like: > > created_on | timestamp without time zone > show_name | text > id_show | integer > show_type | text > id_show_subtype | integer > You can try to divide this into 2 selects: First, select the last 10 entered show, this is simple. Then, write a stored proc. Within, select for every show_type the 2 last events. Both results combine with UNION ALL. I know, the hard part is the function. I havn't time at the moment to write an example, we have guests... Andreas -- Andreas Kretschmer Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header) GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net
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