""Marcin St�pnicki"" <mstepnicki@gmail.com> wrote in message
news:pan.2007.05.22.12.41.38.862364@gmail.com...
...
>
> I think that you either misunderstood this statement or try to break your
> application in a nasty way ;). Please tell us more about your problem
> and/or what do you want to achive, because sequences behave this way for a
> reason (concurrency issues). Perhaps there is another solution.
I have a table with a serial primary key aoto generated by a sequence. I
add/remove records. At a moment I'd like to know what is the current value
of the sequence. I don't wish to know this in the same session where I
add/remove records.
My Postgresql version is "PostgreSQL 8.2.3 on i686-pc-mingw32, compiled by
GCC gcc.exe (GCC) 3.4.2 (mingw-special)", on Windows XP OS, and I use
pgAdmin to open sessions on my database.
With this environment, try the following scenario:
Make a demo table:
CREATE TABLE "tbFoo"
( "ID" integer NOT NULL DEFAULT nextval('"tbFoo_ID_seq"'::regclass)
)
At the beginning, no record are inserted in the table. I call:
SELECT currval( pg_get_serial_sequence('"tbFoo"','ID') );
This rise the following error: ERROR: currval of sequence "tbFoo_ID_seq" is
not yet defined in this session
SQL state: 55000
Then I add a record there:
INSERT INTO "tbFoo" DEFAULT VALUES;
I call SELECT currval( pg_get_serial_sequence('"tbFoo"','ID') ), and I get
1. That's ok because I just use indirectly a nextval to that sequence in the
insert process, on this session.
I close the session, and I open another one.
I call SELECT currval( pg_get_serial_sequence('"tbFoo"','ID') ), and I get
the error again:
ERROR: currval of sequence "tbFoo_ID_seq" is not yet defined in this session
SQL state: 55000
Sabin
