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I've been following the "Beginners Guide to pgRouting" in an attempt to create an in-house application that provides drive-time isochrones. I have a server, postgreSQL and PostGIS and pgRouting - no problem. I have drivers to I can talk to the database from ASP.Net pages - easy again. I've got the data from OS too - imported shapefiles into the database - all easy.

Now I've run the bits of code in that article and the first two are easy again (and quick) so I've got my Node table and the road_ext view OK. However the third statement that creates the "Network" table is killing me, or more specifically the server. I have been trying with just the OS Grid tile "SO" which is not the most remote part of the UK by any means but still not going to have anything like as many roads as the London / Birmingham / Manchester area tiles surely. I'm running it on a quad-core box with a decent chunk of RAM, it's been running for 15 hours and not done yet. Box is not doing anything else, it's dedicated to the task. Even a little tile like the tip of Scotland (John O'Groats) took about 3 hours. At this rate I'm looking at over a week to build a network which is ridiculous. Am I doing anything obviously wrong here or is it just going to take that long and I have to deal with it.

Ultimately I want to produce these polygons and overlay them on Bing Maps. If I have gone off-course above, could anyone please suggest an alternate dataset like OSM or something that's ready made I can use?

Thanks, Michael

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It's been a while since "Beginners Guide to pgRouting" and I have learned a lot of new things since then. The information is spread over my follow-up posts on pgRouting: underdark.wordpress.com/tag/pgrouting. I'm planning to update the beginners guide with what I've learned in the close future. –  underdark Oct 12 '11 at 10:38
    
Yes, I've been following all the things you've covered with interest - you're doing almost exactly what I want to do with routing, catchment areas and so on. I just can't find a machine powerful enough to build a network for the whole UK in order to use your stuff in a production environment. I either need more patience, more time or a pre-built network! –  Michael Oct 12 '11 at 12:56
    
Which OS (Opendata) dataset are you using Merdian2? or Vector District? –  Mapperz Oct 12 '11 at 14:43
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In passing, I think that the OS VectorMap District roads layers are intended for mapping, not routing. They have gaps in the lines, for example where one road crosses under another one. N. –  nhopton Feb 21 '13 at 9:15
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Did you ever resolve this? I'm also trying to create the network table (12 days and counting) from the VectorMap District road layer. I'm beginning to conclude that OS doesn't have an OpenData product which lends itself to routing –  Adrian Oct 21 '13 at 10:38

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