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Link two datasets into lines between nearest points

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Aandrewxhill
Last edited Jul 11, 2013
Created on Jul 11, 2013

The visualization connects two point datasets by drawing a line between each point in one set and its nearest neighbor in the other. A nested SQL query computes the closest geometry for every row using the `<->` distance operator and `ST_MakeLine` to construct the connecting lines. The map renders the resulting `the_geom_webmercator` lines in CartoDB, pairing Citibike stations with points from a second dataset. The approach highlights spatial proximity relationships through direct, nearest-neighbor linkages.

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