Re: OID Usage

On Fri, Jan 14, 2005 at 10:32:18AM +0100, Christian Kratzer wrote:

> $query = sprintf("SELECT currval('%s_%s_seq') AS
> id",$this->table,$this->id_column);

PostgreSQL 8.0 will have a pg_get_serial_sequence() function that
returns the sequence name for a particular column so you don't have
to construct it. This is useful when a table or column has been
renamed, in which case the above will probably break.

CREATE TABLE foo (fooid serial);
ALTER TABLE foo RENAME TO bar;
ALTER TABLE bar RENAME fooid TO barid;
\d bar
Table "public.bar"
Column | Type | Modifiers
--------+---------+--------------------------------------------------------
barid | integer | not null default nextval('public.foo_fooid_seq'::text)

SELECT pg_get_serial_sequence('bar', 'barid');
pg_get_serial_sequence
------------------------
public.foo_fooid_seq
(1 row)

INSERT INTO bar VALUES (DEFAULT);
SELECT currval(pg_get_serial_sequence('bar', 'barid'));
currval
---------
1
(1 row)

--
Michael Fuhr
http://www.fuhr.org/~mfuhr/