How can normalizing database tables help improve data handling and query efficiency in PHP applications?

Normalizing database tables can help improve data handling and query efficiency in PHP applications by reducing data redundancy and ensuring data integrity. This can lead to smaller table sizes, faster query execution times, and easier maintenance of the database structure.

// Example of normalizing a database table in PHP using SQL queries
// Create a new table for storing unique values
CREATE TABLE categories (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(255) NOT NULL
);

// Update the original table to reference the new table
ALTER TABLE products
ADD COLUMN category_id INT,
ADD CONSTRAINT fk_category
    FOREIGN KEY (category_id)
    REFERENCES categories(id);