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Here is my question: Does anyone know why OSM has different attribute values from the same element and same frame time?

The example explains itself, when I try the Shapefile from different mirrors like Planet.osm.org , bbbike.org and geofabrik.de; I find that they have a mistake with the Direction of Travel on its attribute value.

When I check in the website: here the link , I see on its attribute value that there is no mistake at all and has its right value.

Example

So, I thought that those mirrors extract the exact information from osm servers, but I think that there is a lack of info. Is that right?

Thanks for your time,

juasmilla
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    Have you tried QGIS? My guess is that ArcGIS is not interpreting the type of data in that field correctly and dropping the '-' – DPSSpatial_BoycottingGISSE Jun 05 '14 at 16:02
  • I'll try, but it's really strange.. :( – juasmilla Jun 05 '14 at 16:09
  • Do report back! I'm curious myself... – DPSSpatial_BoycottingGISSE Jun 05 '14 at 16:22
  • Installed QGIS 2.2 and opened the files, but the same. It has just only 0 and 1 values.@mapBaker – juasmilla Jun 05 '14 at 20:24
  • I tried and I tried till success. @mapBaker What I tried the last time what the GEOFABRIK shape file into QGIS 2.2, but What I really have to do is Install a OSM plugin to QGIS, then Import de .map file, and Export again to a ESRI Shape file. So, finally, I have the original attribute values from osm into a shapefile (with YES/NO/_/-1 ONEWAY values). I hope it will be usefull these tips. Thanks! Here the link – juasmilla Jun 06 '14 at 20:07
  • that's interesting - I wonder why it needs all those steps! I would have thought any of the exports (geofabrik, etc.) would have handled that, so as the comments below read, you should send this in as a bug! Could be a valuable lesson and something to fix to benefit all! Thanks for the update! – DPSSpatial_BoycottingGISSE Jun 06 '14 at 20:17

2 Answers2

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Metadata is data about data - the coordinate system of a layer, what the allowable attribute values are, or what a given attribute is/means. In a shapefile (which is a database) what you're asking about is an attribute. However in the OSM data this information is stored as tags because it is xml (Extensible Markup Language) document and not a database. See this related question: shapefile terminology for key-value pair

As for your question, it appears that something in the extraction process that converts the xml to a database is dropping the negative sign. This could be by design or a bug / error. You would have to contact one of the organizations doing the conversion and go through their help/support system to report or determine what is going on (unless somewhere here knows something - you may want to edit your question to use the correct terminology).

The alternative would be to process the OSM data to a shapefile yourself, so you know exactly what conversions are being made.

Community
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Chris W
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  • Yes, as you said, we're talking about an attribute, sorry for the mistake.The best thing, as you recommend is to contact directly to OSM staff, maybe they will provide a solution. I was wondering to examinate the XML files from my OSM area of interest, to try getting the information from there, or at least to try updating the mistaken info. I'll comment as I get some news. Thanks @ChrisW for your help. – juasmilla Jun 05 '14 at 21:36
  • Solved with QGIS software and a OSM plugin. Import .map and then Export to Shape file. Much more easy than I expected. – juasmilla Jun 06 '14 at 20:09
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You have to distinguish between the Openstreetmap database and the extracts that are based on it.

The website shows the current content of the database. With the link "Download XML" you can download the xml, and import it into QGIS using the OpenStreetMap plugin or "Add Vector Layer".

The pbf files from Geofabrik offer you the same database content, cut to a certain region.

The shapefiles however are postprocessed data, stored in a way GIS can handle it easier. You may have encountered a bug in that postprocessing, maybe they did not think of negative values for oneway.

But that is not a fault of OSM, rather of the maintainer of the shapefile.

I don't know who makes the other shapefiles you mention, maybe they are the same, or use the same script.

AndreJ
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