Re: ERROR: could not open relation with OID 2836

Rodrigo Gonzalez <rjgonzale(at)gmail(dot)com> writes:
> pg_dump is working fine now, the problem appear with the pg_buffercache
> query...without it I dont notice anything wrong with DB....but of course
> there is something wrong. Can be pg_buffercache the problem?

Oh ... looking again at your latest problem query, the query is buggy:

db=# SELECT ... pg_relation_size(c.relname) ...
FROM pg_class c INNER JOIN pg_buffercache b ON b.relfilenode = c.relfilenode ...
ERROR: relation "pg_toast_1255" does not exist

The pg_toast schema isn't in your search path so you can't just do
"pg_relation_size(c.relname)". You'd be better off using
pg_relation_size(c.oid) anyway.

I was misled by the chance coincidence that pg_proc's toast table was
the one mentioned, otherwise I'd probably have seen this sooner.

So this is not a bug, and not related to the original problem. We still
don't know what the original problem was, but I wonder if it might have
been of the same ilk. I don't think you ever showed us the exact query
that led to the "could not open relation" message?

regards, tom lane