Marc Gehling <m(dot)gehling(at)saphirarcus(dot)de> writes:
> when i read the pg_user, the same error comes ( 6.5.3 Postgresdb)
> tipdb=> select * from pg_user;
> ERROR: cache lookup for userid 201 failed
Hm. It sorta looks like you deleted the pg_shadow entry for the
Postgres superuser. That was not a good idea :-(. You may be
able to recover by re-adding an entry with the same userid.
regards, tom lane