Bruno Wolff III <[EMAIL PROTECTED]> writes: > I am not sure how to check if the supplied function for converting > a timestamp with time zone to a timestamp without timezone using a > specified time zone is immutable. I think this function should be > immutable, but that it probably isn't.
Yup. In 7.4: regression=# select provolatile from pg_proc where oid = 'timezone(text,timestamptz)'::regprocedure; provolatile ------------- s (1 row) regression=# This is a thinko that's already been corrected for 8.0: regression=# select provolatile from pg_proc where oid = 'timezone(text,timestamptz)'::regprocedure; provolatile ------------- i (1 row) regression=# If you wanted you could just UPDATE pg_proc to correct this mistake. Another possibility is to create a function that's an IMMUTABLE wrapper around the standard function. Looking at this, I realize that date_trunc() is mismarked: the timestamptz variant is strongly dependent on the timezone setting and so should be STABLE not IMMUTABLE. Ooops. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 7: don't forget to increase your free space map settings