参考サイト
CREATE OR REPLACE PROCEDURE public.exception_test()
LANGUAGE 'plpgsql'
AS $BODY$
BEGIN
--RAISE EXCEPTION 'exception test 1';
RAISE EXCEPTION 'exception test 2' USING ERRCODE = '0A000';
--RAISE EXCEPTION SQLSTATE '0A000' USING MESSAGE = 'exception test 3';
EXCEPTION
WHEN OTHERS THEN
RAISE NOTICE 'SQLSTATE:% SQLERRM:%', SQLSTATE, SQLERRM;
END;
$BODY$;