Referencial actions

Referencial actions in RND are actions that should happen to a record when a related record is being deleted.

In the example below, an order_details table references orders table and it has a Foreign key on the order_id column. It tells database that if an order is deleted from the orders table, related record in order_details table should be deleted as well.

CREATE table orders (  
	order_id INT PRIMARY KEY,  
	customer_id INT,  
	order_date DATE,  
)  
  
CREATE table order_details (  
	detail_id INT PRIMARY KEY,  
	order_id INT,  
	product_ID INT,  
	quantity INT,  
	FOREIGN KEY (order_id) REFERENCES (order_id) ON DELETE CASCADE  
)