I tried stable, and that didn't help at all. How long does PostgreSQL
maintain the "state" of the function when using immutable? Until a
restart? Until the end of a session? Until the function is dropped and
re-added?
While this value isn't 100% absolutely positively guaranteed to never
change, it is pretty dang close. I have a strict correlation between
the username that someone uses to login and the ID returned. Changing
someone's username would break a whole lot more than this one app on the
project...
Erik Jones wrote:
Tom Lane wrote:
John McCawley <nospam@xxxxxxxxxxxx> writes:
I think I got it:
CREATE FUNCTION new_get_emp_id() RETURNS INTEGER AS $$ select emp_id
from secureview.tbl_employee where username = (SELECT current_user)
$$ LANGUAGE SQL IMMUTABLE;
I made the function immutable so it only calls it once, therefore no
longer requiring a call per-row.
Since it's obviously *not* immutable, this will come back to bite you
sooner or later (probably sooner). Labeling it STABLE would be
reasonable, although I'm not certain how much that helps you. Do you
have indexes on the columns it's being compared to?
Besides, a temp table is pretty much a session variable.
