Hi 2016-03-02 19:31 GMT+01:00 Alexander Farber <alexander.far...@gmail.com>:
> Thank you all for the valuable replies. > > I've also got suggestions to use IS NOT DISTINCT FROM or STRICT at > http://stackoverflow.com/questions/35742865/how-to-ensure-that-a-stored-function-always-returns-true-or-false > > > but the former has the edge case of NULL=NULL returning TRUE > and with the latter I would have to be careful with the way I call my > function - > and I am worried I might forget it later and this is a security related... > > So I will probably use this function: > > CREATE OR REPLACE FUNCTION check_user(in_social integer, > in_sid varchar(255), > in_auth varchar(32)) > RETURNS boolean AS > $func$ > SELECT CASE > WHEN in_social IS NULL THEN FALSE > WHEN in_sid IS NULL THEN FALSE > WHEN in_auth IS NULL THEN FALSE > ELSE (MD5('secret word' || in_social || in_sid) = in_auth) > END; > > $func$ LANGUAGE sql IMMUTABLE; > this solution is ilustrative, but probably slower I hope so function REATE OR REPLACE FUNCTION check_user(in_social integer, in_sid varchar(255), in_auth varchar(32)) RETURNS boolean AS $func$ SELECT COALESCE(MD5('secret word' || in_social || in_sid) = in_auth, FALSE) $func$ LANGUAGE sql IMMUTABLE; should to return same result quckly. Regards Pavel > > Regards > Alex > > > > > >
