Re: drop table cascade doesn't drop manual sequences

On 10/10/07, Guilherme <antoniolo(at)gmail(dot)com> wrote:
> Hello folks,
>
> I'm new to postgres and I'm using version 8.1
>
> Here's the problem anyway:
>
> If I insert a sequence later on table creation with alter table, drop
> table cascade simply doesn't drop this sequence even when I specify
> CASCADE.

This is normal.

> works
> ####################
>
> create table bla(id serial);
> drop table bla CASCADE;
> select * from pg_class were relkind = 'S' => nothing

Here, the sequence was created as a dependent object of the table.

> doesn't
> ####################
>
> create table bla(id integer);
> create sequence bla_id_seq;
> alter table bla alter column id set default nextval('bla_id_seq');
>
> drop table bla CASCADE;
> select * from pg_class were relkind = 'S' => 'bla_id_seq'

Here the sequence was created independently. this method is often
used when a sequence needs to be shared by >1 table:

create table bla(id integer);
create table bla2(id integer);
create sequence bla_id_seq;
alter table bla alter column id set default nextval('bla_id_seq');
alter table bla2 alter column id set default nextval('bla_id_seq');

Now, if i drop table bla2 should I lose the sequence that I assigned
to be used by bla?