Aperçu des sections

• Setting Up SQL Foreign Key Constraints

  Setting Up SQL Foreign Key Constraints

  Content Type
  Video

  Duration
  6m

  Level
  Introductory

  Explore how foreign key constraints help maintain data integrity in relational databases, and see how to set them up in InterSystems IRIS® data platform.
• Code Used in This Video

  Code Used in This Video

  Reference	Timestamp	Code
  Creates an Order table that cascades updates of reference column values to the foreign key column. If a reference column value is deleted, the corresponding foreign key values are set to NULL.	3:01	Begin code: CREATE TABLE Order ( OrderID INT, OrderItem VARCHAR, OrderQuantity INT, CustomerNum INT, CONSTRAINT OrderPK PRIMARY KEY (OrderID), CONSTRAINT CustomersFK FOREIGN KEY (CustomerNum) REFERENCES Customers (CustID) End code,
• What's Next?

  What's Next?
  • See how to define a foreign key in InterSystems IRIS (documentation, 10m).
  • Read more about foreign key constraints in InterSystems IRIS (documentation, 5m).
  • Read about foreign key referential actions (documentation, 5m).
  • Learn about using SQL in InterSystems IRIS (learning path, 3h).