dynamic query

[Michael Kleih]

Ricardo Wagner Martins wrote:

> Hi all,
>
> How can I do a dynamic statement in a CLASS-object
> in the map-file?
> There seem to be only static values possible in use
> with EXPRESSION like this one:
>
> LAYER
>   NAME cities # the CGI-relation
>
>   ...
>
>   CLASSITEM  'population' #something like this
>
>   CLASS
>    EXPRESSION ([POPULATION] > 10000)
>      ....
>    COLOR #e.g. red
>   END
>
>   CLASS
>      EXPRESSION ([POPULATION > 50000)
>      ...
>      COLOR # e.g. dark red
>   END
> END
>
> I wanted to use dynamic (CGI-input) values
> instead of fixed values. How can I do it
> here or is this just the wrong way to solve
> a problem of dynamic input? Any help is
> welcome and appreciated.
>

You could use the PERL-mapscript language.
(see http://mapserver.gis.umn.edu/mapscript.html, you
need to work on classObj)
This allows
you to modified all parameters defined in your .map-file.

Otherwise, you also could change your .map-file with
every access to your web-page.

Michael