Hi, On 2018-06-28 08:55:21 +0200, Laurenz Albe wrote: > Rambabu V wrote: > > While taking pgdump we are getting error message cache lookup failed for function 7418447. > > While trying select * from pg_proc where oid=7418447 returns zero rows. Please help us on this. > > That means that some catalog data are corrupted. It does *NOT* have mean that. You can get such reports e.g. because there was concurrent DDL. Most things are protected against via locks, but there's enough of a window between getting the list of objects and locking to cause issues for tables. And for functions it's fairly easy to get into trouble because there's a mismatch between the snapshot pg_dump uses (a normal transactional snapshot) and the snapshot used to deparse expressions etc (a fresh catalog snapshot that takes into account concurrent commits). Greetings, Andres Freund