Re: Stored procedure declared as VOLATILE => no good optimization is done

Tatsuo Ishii <ishii@postgresql.org> writes:
> So can I say "if a function is marked IMMUTABLE, then it should never
> modify database"? Is there any counter example?
> It seems if above is correct, I can say STABLE functions should never
> modify databases as well.

Both of those things are explicitly stated here:
http://developer.postgresql.org/pgdocs/postgres/xfunc-volatility.html

            regards, tom lane