Re: pg_dumpall problem - duplicated users

"Bartek GRUbY" <grubby@epf.pl> writes:
> i have similar problem - can't make dumps of any db with the same error message (and all applications using this pg
serverworks fine) . But in my case, i think, only user 'postgres' is duplicated: 

> template1=> select * from pg_catalog.pg_shadow where usename = 'postgres';
>  usename  | usesysid | usecreatedb | usesuper | usecatupd |               passwd                | valuntil |
useconfig
>
----------+----------+-------------+----------+-----------+-------------------------------------+----------+-----------
>  postgres |        1 | t           | t        | t         |                                     |          |
>  postgres |        1 | t           | t        | t         | md5c084502ed11efa9d3d96d29717a5e555 |          |
> (2 rows)

What PG version are you using exactly?  Could we see the system columns
for those rows, ie,

    select ctid,xmin,xmax,cmin,xmax,* from pg_shadow where usename = 'postgres';

            regards, tom lane