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The Data I have:

  • Bridges (line layer)
  • Municipal_roads (line layer and does not include information in Bridges)
  • State_roads (line layer that doesn't include Municipal_roads or Bridges)


Since these layers are continuously getting updated/upgraded especially in construction season; what is the 'best of practice' way to connect these layers to produce one layer for routing purposes?

Edit: I would like to, if possible avoid merging the layers.

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Do you use a database? Are the layers aware of each other - as in: are the edges split at all necessary intersections? –  underdark May 6 '13 at 15:43
@underdark Yes, the layers ar in SHP and PostGIS. The layers complete each other, so in the example of a Bridge, the road layer's last and first vertices on the link will correspond to the bridge begin and end point. Also, the bridge layer has a road_on attribute. –  dassouki May 6 '13 at 21:40
pgRouting should be happy enough to use a view which simply unions the three tables. Have you tried that? –  underdark May 7 '13 at 5:40

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