Tatsuo Ishii <is...@postgresql.org> writes: > I'm wondering if we could detect a funcion has a side effect, > i.e. does a write to database.
> Currently we have three properties of functions: IMMUTABLE, STABLE and > VOLATILE. According to docs IMMUTABLE or STABLE functions do not write > to database. Those classifications are meant as planner directives; they are NOT meant to be bulletproof. Hanging database integrity guarantees on whether a "non volatile" function changes anything is entirely unsafe. To give just one illustration of the problems, a nonvolatile function is allowed to call a volatile one. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers