What is the concept of referential integrity and how is it enforced in database design?

Referential integrity ensures that relationships between tables are consistent. Specifically,

it ensures that a foreign key in one table must match a primary key or a unique key in

another table. This prevents invalid references from being made.

• Enforcing Referencing Integrity:
• Use foreign keys to create relationships between tables.
• Enforce actions like ON DELETE CASCADE, ON UPDATE CASCADE, or

ON DELETE RESTRICT to define how changes in parent tables affect related

child tables.

Example:

• A Foreign Key in the Orders table references the CustomerID in the Customers

table. If you try to delete a customer that has associated orders, referential integrity

will prevent the delete unless actions like CASCADE are specified.