What potential issues can arise when using RewriteRule in PHP to create clean URLs?

One potential issue when using RewriteRule in PHP to create clean URLs is that the rewritten URL may not match the actual URL structure of your application, leading to 404 errors. To solve this issue, you can use the $_SERVER['REQUEST_URI'] variable to dynamically generate the clean URL based on the actual URL structure of your application.

RewriteEngine On
RewriteBase /

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php?url=$1 [QSA,L]