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Is it possible to calculate the spaces between the roads using a select statement in a PostGIS/PostGre Database? I tried using some combinations of the predefined functions as ST_Intersects & ST_Difference but did not succeed yet. I would appreciate every help.

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Could you be more precise? What do you mean by spaces? Areas? – Vladimir Oct 24 '12 at 3:57
When you say 'spaces', do you mean a) the closest the roads ever come to each other b) the furthest the roads are away from each other c) some measure of average distance between the two roads or d) the area of the space formed from a polygon composed by having each road as two sides of the polygon and an additional one or two sides to complete it? – Jayden Oct 24 '12 at 4:00
d) the polygons trapped between street network – Marwa Hack Oct 25 '12 at 16:27

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