Re: multi-table unique index

В Пнд, 23.06.2003, в 20:34, Michael A Nachbaur пишет:
> On Monday 23 June 2003 11:16 am, Markus Bertheau wrote:
> > В Пнд, 23.06.2003, в 19:32, Michael A Nachbaur пишет:
> > > Instead of using the "serial" datatype, you can set it to "int4 PRIMARY
> > > KEY DEFAULT nextval(foo_type_id_seq)" and you can manually create the
> > > sequence "foo_type_id_seq".
> > >
> > > This way all the tables share the same sequence.
> >
> > Yeah, but I want to force this behaviour. so that it cannot happen by
> > accident when you insert records without relying on the sequence.

> If you want to ensure that a value is unique when a record is inserted, even
> if the user explicitly specifies an ID values, you can create a unique
> trigger on the tables, but this depends on what you want to do.

I believe what you described is what I want to do. What's a unique
trigger, though?

--
Markus Bertheau.
Berlin, Berlin.
Germany.