A trigger that insures that the member balance in the Member

A trigger that insures that the member balance in the Membership table is not less than -20.00.

Solution

CREATE TRIGGER MembershipTrigger
ON Membership
AFTER INSERT, UPDATE
AS
BEGIN
IF EXISTS(SELECT * FROM INSERTED WHERE balance < -20)
BEGIN
RAISEERROR(\"Balance cannot be less than -20\");
ROLLBACK;
END
ELSE
BEGIN
IF EXISTS(SELECT * FROM UPDATED WHERE balance < -20)
RAISEERROR(\"Balance cannot be less than -20\");
ROLLBACK;
END
END;