Thread: pgadmin 3

In pgadmin3 I'm tring to add auto_inc column like this

ALTER TABLE public.modems  ADD COLUMN id serial;

But get this error :

NOTICE:  ALTER TABLE will create implicit sequence "modems_id_seq" for "serial" column "modems.id"

ERROR:  adding columns with defaults is not implemented
HINT:  Add the column, then use ALTER TABLE SET DEFAULT.


How to add auto_inc fields... thanx

PS. Can I use OID column for primary/foreign functionality, or it
has some restriction ...i mean i may not use auto_inc field ?

Hello,
try alter table modems add column id serial set default

Set default tells postgres to automatically fill in the column data using a sequence on your behalf.

OID could be used for primary key I suppose.  To use as a foreign key you would manually have to somehow copy the value
intable A and insert into B.  AFAIK system generated OIDS are unique to each table. 

HTH

mike
> In pgadmin3 I'm tring to add auto_inc column like this
>
> ALTER TABLE public.modems  ADD COLUMN id serial;
>
> But get this error :
>
> NOTICE:  ALTER TABLE will create implicit sequence "modems_id_seq" for "serial" column "modems.id"
>
> ERROR:  adding columns with defaults is not implemented
> HINT:  Add the column, then use ALTER TABLE SET DEFAULT.
>
>
> How to add auto_inc fields... thanx
>
> PS. Can I use OID column for primary/foreign functionality, or it
> has some restriction ...i mean i may not use auto_inc field ?
>
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Don't 'kill -9' the postmaster

On Wed, Jul 21, 2004 at 12:06:09AM -0500, Mike G wrote:
> OID could be used for primary key I suppose.  To use as a foreign key
> you would manually have to somehow copy the value in table A and
> insert into B.  AFAIK system generated OIDS are unique to each table.

WRONG. OIDs are not guarenteed unique. They are not suitable for
primary keys. They will wrap eventually. They are not indexed in any
way unless you create an index yourself.

Use serials from primary keys, much safer...
--
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> Patent. n. Genius is 5% inspiration and 95% perspiration. A patent is a
> tool for doing 5% of the work and then sitting around waiting for someone
> else to do the other 95% so you can sue them.