全局$ wp_query; 返回空

Firstly this question is different to this one as I'm talking about accessing $Wp_Query from outside of a loop.

What I'm trying to do

I'm currently just attempting to make an ajax request from a script to a php file called database.php which looks like so.

if (isset($_GET["increase"])) {
    global $wp_query;

    echo var_dump($wp_query);

}

As seen I'm just trying to get anything from the $wp_query this is the output from log.

 XHR finished loading: GET "http://localhost/WCBD/wp-content/themes/Test%20Computing/database.php?increase=1".jquery.js?ver=1.11.1:4 m.ajaxTransport.sendjquery.js?ver=1.11.1:4 m.extend.ajaxjquery.js?ver=1.11.1:4 m.each.m.(anonymous function)myscripts.js?ver=1.2:15 foo.vote_up(index):313 onclick
myscripts.js?ver=1.2:11 
NULL

So it seems that it loaded correctly.

I feel like I'm missing an obvious step or something at being able to access the $wp_query.

Thank you.

You'd better to make any function within "action". $wp_query will be initiated already, if you make:

add_action('init','your_func');function my_func(){
    global $wp_query;
    var_dump($wp_query);
    // or  var_dump($GLOBALS['wp_query']);
}