Thread: sequences TODO items
Hi, i'm looking for some item i can do and that have enough consensus to make it worth the effort... :) * Have sequence dependency track use of DEFAULT sequences, seqname.nextval? what this means? i don't understand it... * %Disallow changing default expression of a SERIAL column? why? a SERIAL is not really a datatype but a short-hand to make an integer with a nextval's sequence as default... so why making them both (the integer type and the nextval's sequence as default) act as if it were a single unit? Actually, i have dropped sequences created with SERIAL because i found that was better to me to make it manually... -- regards, Jaime Casanova (DBA: DataBase Aniquilator ;)
Jaime Casanova wrote: > Hi, > > i'm looking for some item i can do and that have enough consensus to > make it worth the effort... :) > > * Have sequence dependency track use of DEFAULT sequences, seqname.nextval? > > what this means? i don't understand it... The idea is to automatically add a dependency of the sequence on the table using it as a default. > * %Disallow changing default expression of a SERIAL column? > > why? a SERIAL is not really a datatype but a short-hand to make an > integer with a nextval's sequence as default... so why making them > both (the integer type and the nextval's sequence as default) act as > if it were a single unit? > Actually, i have dropped sequences created with SERIAL because i found > that was better to me to make it manually... Well, SERIAL adds dependency information, so if you drop the table, the sequence is dropped. If you change the default for a serial type, the dependency on the sequence should go away. -- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610) 359-1001+ If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania19073
On Fri, Sep 02, 2005 at 04:57:52PM -0400, Bruce Momjian wrote: > Jaime Casanova wrote: > > Hi, > > > > i'm looking for some item i can do and that have enough consensus to > > make it worth the effort... :) > > > > * Have sequence dependency track use of DEFAULT sequences, seqname.nextval? > > > > what this means? i don't understand it... > > The idea is to automatically add a dependency of the sequence on the > table using it as a default. Yeah, the point is that if you treat the sequence name as a text literal, there's no way to track dependency information. On the other hand, if it were treated as, say, an OID, then we could track the dependency. In order to do that, we need to change the representation of the DEFAULT for a serial column. Instead of the seqname.nextval expression we could use SQL:2003 syntax, which is something like "NEXT VALUE FOR seqname". -- Alvaro Herrera -- Valdivia, Chile Architect, www.EnterpriseDB.com "Si un desconocido se acerca y te regala un CD de Ubuntu ... Eso es ... Eau de Tux"