setting the url to a function in a custom module I am trying to make a link in a view which, when clicked on, will call a function in a custom module to make a database call. I have made a link by making a Global:custom text field (because thats the way it seemed I had to do it from some posts online), set it to a path accompanied with some arguments. I made a custom module used the hook_menu: 

function example_menu() {
$items = array();
$items['path_name'] = array(
'title' =&gt; t('Example'),
'page callback' =&gt; 'my_callback',
'access arguments' =&gt; array('access content'),  
'type' =&gt; MENU_CALLBACK,
);
return $items;
}


where function my_callback does a database call.

When I click on the link I just get a blank page with nothing on it. Which pieces am I missing here? The first thing I thought was that I needed to route the link to a page (hence the name 'page_callback') but how would I do this? All I really want done is a database call, I don't mind if you stay on the same page.

EDIT:
Additionally, what I have found is that on the content management page there ares some errors on top which tell me that I'm missing arguments 1 through 4 (there were four arguments), which definitly can be part of the problem. The function starts off:

function example_my_callback($staff_action, $first_name, $last_name, $email)


and the url for the link was path_name?staff_action=[varible name found in views]...etc
Is there any issue here?
The page callback must be the name of the function that will return the data from database

You must create a function like this :

function my_callback(){
// here you will connect and pull up data from the database
return $your_data;
}


Also don't forget to clear the cache and read about the database API here