Working with Procedures

CREATE OR REPLACE PROCEDURE archive_orders
(cust_id IN NUMBER
,retention IN NUMBER) IS
BEGIN
DELETE orders
WHERE customer = cust_id
AND order_date < SYSDATE - retention;
INSERT INTO maint_log
(action, action_date, who) VALUES
('archive orders '||retention||' for '||cust_id
,SYSDATE ,USER);
END;

EXEC DBMS_OUTPUT.PUT_LINE('Hello world!');
CALL DBMS_OUTPUT.PUT_LINE('Hello world!');