I am planning to deal with all of the following TODO items today:
* pg_database should have unique indexes on oid and on datname.
* pg_shadow should have unique indexes on usename and on usesysid.
* pg_am should have unique index on oid
* pg_opclass should have unique index on oid
* pg_amproc should have unique index on amid+amopclaid+amprocnum
* Remove pg_rewrite's unnecessary index on oid, delete unused RULEOID
syscache.
* Remove index on pg_listener for performance reasons.
* Change pg_attrdef's nonunique index on adrelid into a unique index
on adrelid+adnum.
Have I missed anything in this line?
regards, tom lane