> -----Original Message----- > From: Andrew Sullivan [mailto:[EMAIL PROTECTED] > Sent: Donnerstag, 13. Jänner 2005 20:49 > To: 'pgsql-sql@postgresql.org' > Subject: Re: [SQL] Column with recycled sequence value > ... > > used 2^32 will be reached soon and then? There are far less > than 4G-records > > saved thus these values may be reused. How can this be accomplished? > > You can set the sequence up to cycle (so once it gets to the end, it > wraps around to the beginning again). The keyword is CYCLE at CREATE > SEQUENCE time. It defaults to NO CYCLE. > > One potential problem, of course, are collisions on the table, > because some value wasn't cleared out. It sounds like you don't have > that problem though.
actually I am asking just because of that. The thing is, that I am able to synthetisize wonderful SELECTs but I have no unterstanding of how to first find out wether a record doesn't exist in order to create it in the same transaction. As user of procedural languages I'm thinking of variables and so on. But AFAIK SQL has a way to also find a way without them. OR I'd like to read that I can't use SQL for this purpose and at minimum PL/pgSQL would be appropriate for me. PS. 32-Bit is my bussiness limitation - but also that is thinkable. thanks ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend
