[OpenLayers-Users] Problems with large datasets, WFS, alternatives.

[Phil Scadden]

I have a rather large dataset of lines (1000s of them) which is 
displayed efficiently enough in WMS. The problem comes when I try to 
query them. (Eg everything within a user-created polygon). The query 
works fine, but it returns GML for the geometry and this can be very 
large. Queries become exceedingly slow. I would normally use this GML to 
draw the selected features in a vector layer.

At moment, the only solution I can come up with is query against a 
version of the dataset that has been severely decimated (display proper 
shape in WMS, and query against generalised layer in WFS). A better 
solution??? would be return only non-geometry feature fields and there 
was a way to show the selected feature via a WMS layer. (get server to 
draw the selected features by WMS with filter and show that layer). Is 
this possible?
-- 
Phil Scadden, Senior Scientist GNS Science Ltd 764 Cumberland St, 
Private Bag 1930, Dunedin, New Zealand Ph +64 3 4799663, fax +64 3 477 5232


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