What are the potential drawbacks of including a running number in a string in PHP database design?

Including a running number in a string in a PHP database design can lead to potential issues such as data redundancy and difficulty in maintaining data integrity. To solve this problem, you can use an auto-incremented primary key in your database table instead of a running number in the string. This will ensure each record has a unique identifier without the need for manual management.

CREATE TABLE users (
    id INT AUTO_INCREMENT PRIMARY KEY,
    username VARCHAR(50) NOT NULL,
    email VARCHAR(100) NOT NULL
);