RichGags

I set up a results page which shows me results from my query... $query_WADAproperties = "SELECT id, pic, address, city, state, submarket, type, class, year, buildingsize, floorsize, space, broker, annualrent FROM properties ORDER BY id ASC"; How would I set up the ORDER BY to be a variable so when I click on a column heading on the results page it passes the variable to the php and re-sorts it? I would think that I need to declare a variable that defaults to "id" if nothing is passed to it and put it somewhere .... and make the headings clickable, pointing back to the results.php with a parameter, but have no idea how. Thanks! Rich