In the database design of e-commerce websites, foreign keys are a very common and important concept. It is used to establish relationships between tables to ensure data integrity and consistency. By using foreign keys, we can create referential integrity constraints in the database to ensure the consistency of related data and support various data operations and queries.
In a typical e-commerce website database, there may be many tables, such as product table, order table, user table, etc. There is a certain relationship between these tables. For example, the order table contains user information and product information, and the user table may contain the user's shipping address, etc. In order to establish a relationship between these tables, we can use foreign keys.
Let's take a simplified e-commerce website database as an example to illustrate the use of foreign keys.
CREATE TABLE Users (
id INT PRIMARY KEY,
name VARCHAR(255),
email VARCHAR(