[TCMUG] mapfile filter & variable substitution question

[Jennifer Strahan]

Hi everyone,

I have a question about using the mapfile Filter option with variable 
substitution.  In my user interface (OpenLayers), I have drop down boxes 
that allow users to filter the data display based on selected year and 
selected category.  Accordingly, I have two filters set up in my mapfile:

   FILTER "year = %selected_year%"
   FILTER "category=%selected_category%"

What if the user wants to see data for all years or for all categories?  
Is there a way that I can submit a wildcard in my mapserv URL instead?  
Or is there some other way to do this?  My data source is a PostGIS. 

Regards,
Jennifer


-- 
Jennifer Strahan, GIS Specialist
GreenInfo Network - www.greeninfo.org -
Information and Mapping in the Public Interest

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