15

-- I tried to put these all in a single block like I did previously,
-- but it wanted none of my malarkey.
-- 1.
CREATE OR REPLACE TRIGGER Lab15Trigger1
AFTER DELETE ON studentemp
BEGIN
    INSERT INTO studentemp
    values((select count(*) + 1 from studentemp), 'SpudLord', 100, 'Hobgoblin');
END;
-------------------------------------

-- 2.

ALTER TRIGGER Lab15Trigger1 DISABLE;

-------------------------------------

-- 3.
CREATE OR REPLACE TRIGGER Lab15Trigger2
BEFORE DELETE ON studentemp
DECLARE
counter number;
BIGBOI EXCEPTION;

BEGIN
SELECT COUNT(*)
INTO counter
FROM studentemp;
IF (counter < 20)
THEN
    RAISE BIGBOI;
END IF;

EXCEPTION
WHEN BIGBOI THEN
    RAISE_APPLICATION_ERROR(-20101, 'At least 20 rows in studentemp table needed');
END;

-- testing
DELETE FROM studentemp
where EMPLOYEE_ID = 3;

SELECT * FROM STUDENTEMP;