Is it possible to extend the COALESCE() function? I would like to support for coalescing an int into a Boolean, but I get syntax errors if I don't wrap coalesce in quotes.
CREATE OR REPLACE FUNCTION coalesce(boolean,int) RETURNS boolean AS $$
SELECT CASE WHEN $1 IS NOT NULL THEN $1 WHEN $2 = 1 THEN true ELSE false END
$$ LANGUAGE sql IMMUTABLE;
Thanks,
Dave