cau 11

/* BT1 - Buoi 5 */
-- Phan I:
-- Cau 11:
CREATE TRIGGER trg_Ins_Up_hd ON HOADON
FOR INSERT, UPDATE
AS
BEGIN
    DECLARE @NgayHD smalldatetime, @MaKH CHAR(4)
    SELECT @NgayHD = NGHD, @MaKH = MaKH
    FROM INSERTED
    IF (@NgayHD < (SELECT NGDK FROM KHACHHANG WHERE MAKH = @MaKH))
        BEGIN
            PRINT 'LOL: NGAY HOA DON KHONG HOP LE'
            ROLLBACK TRANSACTION
        END
    ELSE
        BEGIN
            PRINT 'THANH CMN CONG'
        END
END

CREATE TRIGGER trg_Ins_Up_Kh ON KHACHHANG
FOR INSERT, UPDATE
AS
BEGIN
    DECLARE @NgayDK smalldatetime, @MaKH CHAR(4)
    SELECT @NgayDK = NGDK, @MaKH = MaKH
    FROM INSERTED
    IF (@NgayDK > ALL (SELECT NGHD FROM HOADON WHERE MAKH = @MaKH))
        BEGIN
            PRINT 'LOL: NGAY DANG KI KHONG HOP LE'
            ROLLBACK TRANSACTION
        END
    ELSE
        BEGIN
            PRINT 'THANH CMN CONG'
        END
END