I have a column of geometry of type multi-linestring in a database as in the following format

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Now I want to add a new column of speed by mapping GPS points against geometry column (as described below that has been listed on separate CSV file).
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Tell me how I query to merge the speed column (captured against GPS coordinate points) with existing geometries

1 Answer 1


First, you can identify for each point the nearest line by using the postgis ST_Distance function (geometry_point,geometry_line) and a LIMIT 1 to keep only the nearest line.

In a second step, thanks to an attribute join, you will be able to add speed to your lines.

If you need help in executing these requests, don't hesitate to ask.

  • 1
    even better: don't use ST_Distance, use the 'KNN' operator <->: check this answer for an optimized nearest-neighbor search in an UPDATE statement (@HuniyaSohail change accordingly to select the speed column of your points).
    – geozelot
    Dec 9, 2019 at 11:02

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