Re: NEXT VALUE FOR... - Mailing list pgsql-patches

On Fri, 2004-05-07 at 14:38, Tom Lane wrote:
> Rod Taylor <pg@rbt.ca> writes:
> > NEXT VALUE FOR and CURRENT VALUE FOR where CURRENT is an unreserved
> > keyword and VALUE is not reserved in any way (ident with comparison to
> > "value").
>
> I see one pretty big problem with this: the SQL2003 spec says clearly
> that multiple occurrences of NEXT VALUE FOR should all generate the same
> value within a particular row.  (See, eg, last sentence of 4.21.2 or the
<snip>
> Offhand I see no simple way to do what the spec asks for within Postgres
> :-( but that doesn't mean we should ignore the requirement.

You're right. I had missed that.

Does that mean the below insert should give both col1 and col2 the same
value?

CREATE TABLE test (
    col1 integer DEFAULT NEXT VALUE FOR t_seq,
    col2 integer DEFAULT NEXT VALUE FOR t_seq
);

INSERT INTO TABLE DEFAULT VALUES;