PHP - query expression

[Robert Ofarrell]

Currently I am trying to facilitate a query by expression and from a reply
from Daniel I have been working on setting the query expression and
following that with a queryUsingRect() with the coordinates the size of
the map.  However I wish to do this dynamically so my question is, is
there any way to set the query expression of a layer with PHP mapscript?

Any help would be greatly apreciated.

Robert O'Farrell
University of Queensland, Brisbane, Australia