"Gauthier, Dave" <dave.gauthier@intel.com> writes:
> I tried vacuum pg_database, no luck. I shut down and restarted the DB
> and it seems to have fixed the problem. Still, not sure why it happened
> in the first place or how to prevent it in the future.
My recollection is that that's a symptom of lack of vacuuming, in PG
versions that are too old to have automatic defenses against such
DBA misfeasance. Check whether your routine vacuuming procedures
cover the system catalogs...
regards, tom lane