Re: Adding 'serial' to existing column

On Fri, 2017-11-03 at 16:47 -0400, Tom Lane wrote:
> Robert Lakes <robertl(at)propaas(dot)com> writes:
> > I am new to Postgres and I am trying to build this SQL statement in
> > my SQL
> > script:
> > ALTER TABLE listings_cdc ALTER COLUMN table_id SET DEFAULT
> > nextval('tab_id_seq');
>
> That looks correct, but this not so much:
>
> > I am trying to build the above-stated command as a dynamic SQL
> > statement:
> > EXECUTE 'ALTER TABLE listings_cdc ALTER COLUMN table_id SET
> > DEFAULT
> > nextval('||quote_ident(tab_id_seq)||')';
> > I've received an error when running the script this above-stated
> > command:
> > ERROR: column "tab_id_seq" does not exist
> > LINE 1: ...OLUMN table_id SET DEFAULT
> > nextval('||quote_ident(tab_id_seq...
>
> You want quote_literal, not quote_ident, because you're trying to
> produce
> a single-quoted literal.
>
> regards, tom lane
>
>

You could also do:-

ALTER SEQUENCE tab_id_seq OWNED BY listings_cdc.table_id;

which would establish the one-to-one relationship between the table and
its sequence for that column.

My 2 cents worth.

HTH,
Rob