In PHP, what is the significance of using unique identifiers like IDs or ArtNr in database tables and how can they be utilized for better functionality?

Using unique identifiers like IDs or ArtNr in database tables is important for ensuring each record in the table is uniquely identifiable. This helps in maintaining data integrity, simplifying data retrieval and manipulation operations, and avoiding conflicts or inconsistencies in the database. Unique identifiers can be utilized as primary keys in database tables to uniquely identify each record and establish relationships between different tables.

// Example of creating a table with a unique ID as primary key
CREATE TABLE users (
    id INT AUTO_INCREMENT PRIMARY KEY,
    username VARCHAR(50) UNIQUE,
    email VARCHAR(100) UNIQUE
);