nextval.
currval only has value, when sequence wwas used in the session before,
you would use it to obtain last value returened by nextval. read the
manual .
On Sat, Feb 14, 2009 at 11:25 AM, Onno Molenkamp <onno@flox.org> wrote:
> Hi,
>
> I recently upgraded a database from 8.1.11 to 8.3.6, and I noticed the
> following statement stopped working:
>
> insert into test (b) select currval('test_a_seq'::regclass)
>
> given the following table:
>
> create table test (a serial, b int)
>
> The error I'm getting is: "ERROR: currval of sequence "test_a_seq" is not yet
> defined in this session". With a values clause instead of a select, it still
> works as expected, by inserting two identical values:
>
> insert into test (b) values (currval('test_a_seq'::regclass))
>
> Although it's easy enough to work around this problem by also explicitly
> inserting nextval('test_a_seq'::regclass) into column "a", I'm wondering why
> it did work in 8.1 and doesn't work anymore in 8.3.
>
> Is this a bug in either version, was is never supposed to work like this, or
> have I missed a change in the release notes somewhere?
>
> Thanks,
>
> Onno
>
--
GJ