[mapserver-users] Re: [OSGeo-Discuss] MapServer dynamic thematic map

[Stephen Woodbridge]

> jxRui wrote:
>> Folks,
>> I know that MapServer can draw dynamic thematic map(choropleth map) via
>> cgi.  I'd like to develope MapServer app via PHP MapScript to realize
>> the dynamic thematic map. But i find that the PHP MapScript interface
>>  cannot do this.
>> For instance, i have only one polygon layer about U.S states,and this
>> layer has 50 fields in the dbf or in MySQL,the most important thing is
>>  that these attributes values varying everyday. When the user select one
>> of the fields from the droplist component of the MapServer web app in 
>> Firefox or ie
>>  explorer,then the dynamic thematic map wil be drawn automaticly with the
>>  selected fields.
>> What can i do this via PHP MapScript ? I need your help. Thank a lot to
>>  you first!
>>   Best regards
>>   jxRui

I think the first question is where is the state polygon layer stored 
and how is it getting updated?

I would recommend putting it in a PostgreSQL/PostGIS database because:

1) it is easy to load a shapefile into the database
2) it is easy to update the attributes asynchronously to the mapping 
without any issues
3) postGIS is well supported and easy to use from mapserver
4) it is the best way to do dynamic thematic maps

Then in you mapfile you can setup the layer with the appropriate 
connection parameters for postGIS, and you can change the DATA statement 
in php mapscript to select the appropriate SQL to render the map 
thematically.

-Steve W