example of build_query function?

I have this resource: (http://codex.wordpress.org/Function_Reference/build_query), but it does not give full example.

I have this URL:
http://localhost:8888/mypage/?page_id=87

and this array:
array('name' => 'me')

So, I need to add the array to the end of the URL. I know the build_query function will add the proper markup ( & ), but how do I connect the function to the URL. e.g.- How do I use the function?