What are the potential pitfalls of storing permissions in a database instead of using define variables in PHP?

Storing permissions in a database can introduce additional complexity and potential performance issues compared to using defined variables in PHP. It may require additional database queries to fetch permissions for each request, leading to slower response times. Additionally, database connections can fail, causing permission checks to fail unexpectedly. To mitigate these pitfalls, consider caching permissions in memory or using a caching mechanism like Redis to reduce the number of database queries.

// Example of caching permissions in memory using PHP arrays
$permissions = [
    'admin' => ['manage_users', 'manage_posts'],
    'editor' => ['manage_posts'],
    'user' => ['read_posts']
];

$userRole = 'admin';

if (in_array('manage_users', $permissions[$userRole])) {
    echo 'User has permission to manage users.';
} else {
    echo 'User does not have permission to manage users.';
}