Andrew Gierth <andrew(at)tao11(dot)riddles(dot)org(dot)uk> writes:
> "PG" == PG Bug reporting form <noreply(at)postgresql(dot)org> writes:
> PG> (4) update pg_attribute set attmissingval = NULL where attname = 'b';
> Nobody ever claimed that you could update pg_attribute without crashing
> the server; I can think of half a dozen ways to do it.
Specifically, you broke it by not keeping atthasmissing consistent with
attmissingval. Manually corrupting catalogs like that is not a supported
operation.
regards, tom lane