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What are the best practices for importing and aggregating tracks (in my case in 'plt' format) in a PostGIS table, grouped by user. Are there any tools/db models/tutorials available?

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PLT format I don't know.

but to aggregate the points to lines when you have it in PostGIS is easy. use ST_MakeLine

CREATE TABLE tracklines as
SELECT ST_MakeLine(the_geom) as the_geom FROM 
(SELECT * FROM trackpoints ORDER BY timestamp) a GROUP BY user;


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+1 Thanks, that will be really useful after I have imported the points. Since I suppose importing gps tracks is a quite common task I was wondering if there were any tools to automate it. The format may not be a major issue, it can certainly be converted to something else. Google earth can convert them to kml/z easily. Thanks for any additional pointers. – Vladtn Mar 27 '11 at 11:02

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