[Prime8]

You've nailed it Old Pedant, but for the last part, where I call the function is where it falls over. I could, in that function set $a = 'something' just not a $_POST[]. With php, $_POST causes the parser to expect there to be some data that was sent to the server using the same method, and tries to return it. I may have confused the issue there, but my intent was to show the hoped-for end-result.

The problem is basically that I have data fetched from a table using php, but I'd like to perform client side filtering on it via javascript (edit: well, preferably php but from the responses here js looks like the best bet). I need some tool to requery the data client side after it is fetched with php. AJAX will apparently do it (as BubikolRamios) pointed out, but I'm considering JQuery as well. I've been putting off tackling JQuery, so this might be a good time to start.