CREATE OR REPLACE FUNCTION validateEmail(email character varying)
RETURNS BOOLEAN AS $$
BEGIN
	IF (email !~ '^[A-Za-z0-9._%-]+@[A-Za-z0-9-]+[.][A-Za-z]+$') THEN
		RETURN FALSE;
	ELSE
		RETURN TRUE;
	END IF;
END
$$
LANGUAGE PLPGSQL

SELECT validateEmail('yogonza524@gmail..net');