Re: BUG #8247: Duplicate database names - pg_dump backup fails

paul.macdonald@ssc-spc.gc.ca writes:
> Postgres version: 7.4.7-6sarge1

Egad.  Not only has 7.4 been EOL for years, but the last release in that
series was 7.4.30.  You are missing many years' worth of bug fixes.
You really, really, really need to get off of that PG version ASAP.

> Issue: pg_dump fails due to unexpected duplication of database name
> ("avipads"). Dropdb will remove one instance of the database name, but
> unable to remove the second instance.

I suspect this is evidence of transaction ID wraparound in the
pg_database catalog.  See if "VACUUM FULL pg_database" makes things
any saner.  (Delete the one database that you're able to get rid of
first.)

            regards, tom lane