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CREATE TABLE Reservation(
Booking_Number INT NOT NULL,
Room_Number INT NOT NULL,
Date_Reserved DATE NOT NULL,
PRIMARY KEY(Booking_Number, Room_Number, Date_Reserved)
--,FOREIGN KEY(Booking_Number) REFERENCES Booking(Booking_Number),
--FOREIGN KEY(Room_Number) REFERENCES Room(Room_Number)
);
CREATE TABLE Additional_Extra(
Booking_Number INT NOT NULL,
Room_Number INT NOT NULL,
Date_Reserved DATE NOT NULL,
Extra_ID INT NOT NULL,
PRIMARY KEY(Booking_Number, Room_Number, Date_Reserved, Extra_ID)
--,FOREIGN KEY(Booking_Number) REFERENCES Booking(Booking_Number),
--FOREIGN KEY(Room_Number) REFERENCES Room(Room_Number),
--FOREIGN KEY(Extra_ID) REFERENCES Extra(Extra_ID)
);
ALTER TABLE Additional_Extra
Add(
CONSTRAINT test_date
FOREIGN KEY(Booking_Number, Room_Number, Date_Reserved)
REFERENCES Reservation(Booking_Number, Room_Number, Date_Reserved)
);