Cartographica 1.4 can send information along to a WFS server in order to limit the amount of information which is sent back to it. However, this functionality requires knowledge of both the layer information and a bit of how WFS works as well. The additional filter information can be pasted directly into the Filter box in the window and will be passed along to the WFS server as part of the retrieval instructions.
The specifics of what field names, values, and operations are allowed will be dependent upon your particular WFS server, but here is an example that we have used in-house to give you an idea of what these look like:
<ogc:PropertyIsGreaterThan><ogc:PropertyName>DATE_</ogc:PropertyName><ogc:Literal>'2012-09-15'</ogc:Literal></ogc:PropertyIsGreaterThan>
To break this down, the server is to look at the property named "DATE_" and compare it to only allow features which have values greater than '2012-09-15'.
More complex filters are also allowed, basically anything that can be formed with valid WFS, however, they can get complex to format. Here is an example of a filter which looks at the "DATE_" field from above, and also looks at the "SOURCE" field and requires it to be equal to "BIC".
<ogc:And><ogc:PropertyIsGreaterThan><ogc:PropertyName>DATE_</ogc:PropertyName><ogc:Literal>'2012-09-15'</ogc:Literal></ogc:PropertyIsGreaterThan><ogc:PropertyIsEqualTo><ogc:PropertyName>SOURCE</ogc:PropertyName><ogc:Literal>BIC</ogc:Literal></ogc:PropertyIsEqualTo></ogc:And>
It's not simple, but it is effective.
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