Re: Multi row sequence?
От | Bruno Wolff III |
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Тема | Re: Multi row sequence? |
Дата | |
Msg-id | 20041219154040.GB2263@wolff.to обсуждение исходный текст |
Ответ на | Re: Multi row sequence? (Ciprian Popovici <ciprian@zuavra.net>) |
Список | pgsql-general |
On Sun, Dec 19, 2004 at 15:02:27 +0200, Ciprian Popovici <ciprian@zuavra.net> wrote: > On Sat, 18 Dec 2004 11:07:37 -0600 Bruno Wolff III <bruno@wolff.to> wrote: > > On Fri, Dec 17, 2004 at 11:10:12 -0000, > > Filip Wuytack <fwuytack@fgscapital.com> wrote: > > > Is it possible to have a sequence (as a multirow prim key), where > > > sequence (id) only increase per group of data (grp). > > > > Why do you want to do this? It would be a lot simpler to generate unique > > values over the table and that will work just fine if all you need > > is uniqueness. > > Here's a case where what he said would come in handy: arranging a > particular display order within the individual groups. You have the unique > key for the entire table, but you need something like a serial restricted > to just a group of rows. You wouldn't want to use a serial type for that. Inserts would become a big pain. You can use numeric or text so that it is easy to do inserts.
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