url parts in php code example

Example 1: if browser url is having query string after domain name in it check using php

$url = $_SERVER['REQUEST_URI'];

if (!strpos($url,'mysql')) {
echo 'No mysql.'; //swapped with other echo statement
} else {
echo 'Mysql exists.';
}

Example 2: part of url php

//https://www.google.com/search?key=1234
	$url = $_SERVER['REQUEST_URI']; 
    $url_components = parse_url($url); 
    parse_str($url_components['query'], $params); 
    $key = $params['key']; 

// key=1234