Foreign Key - ER Diagram Syntax

  • Type FK to mark a field as foreign key
  • To define a composite foreign key, use the table level FK() syntax
Order
-
OrderID int PK
CustomerID int FK > Customer.CustomerID
TotalAmount money NOT NULL
OrderStatusID int

(or)

Order
-
OrderID int PK
CustomerID int
TotalAmount money NOT NULL
OrderStatusID int
FK(CustomerID,OrderID) > OrderDetail(CustomerID,OrderID)