Question

The WorkOrders table contains a foreign key, ClientNum, which must match the primary key of the Client table. What type of update to the WorkOrders table would violate referential integrity? If deletes do not cascade, what type of update to the Client table would violate referential integrity? If deletes do cascade, what would happen when a client was deleted?

Answer 1

Answer:

Changing the customer number on a record in the Orders table to a number that does not match a customer number in the customer table would violate referential integrity.

If deletes do not cascade, deleting a customer that has orders would violate referential integrity.

If deletes cascade, customer can be deleted and all orders for that customer will automatically be deleted.