Re: BUG #5476: sequence corruption

On 2010-05-27, Piergiorgio Buongiovanni <p.buongiovanni@net-international.com> wrote:
>
> The following bug has been logged online:
>
> Bug reference:      5476
> Logged by:          Piergiorgio Buongiovanni
> Email address:      p.buongiovanni@net-international.com
> PostgreSQL version: 8.3.4
> Operating system:   CentOS (Redhat 5.4)
> Description:        sequence corruption
> Details:
>
> We experimented a sequence corruption on a table:
> If we now look at the sequence data using pgAdmin version 1.8.4, we see the
> following:
>
> CREATE SEQUENCE business.subject_isid_seq
>   INCREMENT 1
>   MINVALUE 1
>   MAXVALUE 9223372036854775807
>   START 58827944
>   CACHE 1;
> ALTER TABLE business.subject_isid_seq OWNER TO netdw_owner;
>
> The problem is that now the search on the table business.Subject (where the
> sequence is used) performs very slowly. It seems the data are corrupted but
> at the end I can see that there is a record created with the number 463663
> instead of 57. As you can see the next value will be used is 58827944.
> Which is the problem? Can I recover this situation and restore the right
> sequence value? I tried to set the START value to 58 but, as you can see,
> the value changed.

have you tried vacuum full on the table?  I get the feeling that it
may have several million deleted rows.

 VACUUM FULL subject;