[Chameleon] Visualize data from other data source in mapfile

[Davelaar, Hilbert]

Hi list,
 
I'm wondering if it is possible to visualize data from another data source in the mapfile. For example, I have a polygon layer with for each polygon a code defined. I also have another data source (e.g. dbf-file, MySQL, MS Acces, etc.) in which this code is also present together with some more information attached to it. Is it possible to visualize this external information in the map to classify the polgyon layer based upon expressions that use the information from the additional data source? In other words, if it possible to join this information for visualization, so that when the other data source is update, the map in the Chameleon application is also automatically updated?
 
Kinds regards,
Hilbert Davelaar