What are the potential pitfalls of including a PHP file in multiple files without using include_once or require_once?

The potential pitfall of including a PHP file in multiple files without using include_once or require_once is that the file may be included multiple times, leading to redeclaration of functions, classes, or variables, causing errors or unexpected behavior. To solve this issue, you can use include_once or require_once instead, which ensures that the file is only included once.

// Use require_once to include the file only once
require_once 'your_file.php';