Summary - Data integrity

Build a consistent table with PRIMARY KEY, FOREIGN KEY and CHECK.

Entity, referential and domain integrity together ensure data consistency. Triggers add custom checks.

-- PRIMARY KEY (entity)
-- FOREIGN KEY (referential)
-- CHECK + NOT NULL (domain)

Summary integrity types.

Exercise Summary - Data integrity

Summary: add a FOREIGN KEY to orders.

Show example solution

ALTER TABLE orders
ADD FOREIGN KEY (customer_id) REFERENCES customers(id)