In MySQL, referential integrity is a concept that maintains the relationship of data across multiple tables for consistency purposes. For instance, in an e-commerce shop, the `category_id` column in the `products` table might refer to the same column in the `product_categories` table. In most cases, you'll implement the consistency of references in different database tables to enforce business logic, validate users' input, and create a more accurate application. This is very useful when you're d......