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If your software doesn't support multi-part features you may have to go to extraordinary and complicated lengths to execute spatial operations. For example, the intersection of two polygons can, in general, have more than one connected component. It is convenient, both algorithmically and conceptually, to suppose that such an intersection returns a single ...


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E00 is a proprietary ESRI file format intended to support the transfer between ESRI systems of different types of geospatial data used in ESRI software ( Old systems anyway, people use the ESRI file geodatabase now ). Usually, people then convert to coverages and work with those, they don't use the E00 file directly (somebody correct me if I'm wrong). I ...


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Imagine joining population data to a table of single-part polygons representing countries. Depending on how you do the join, either every island would get the full population of that country or only one polygon of the set would get the full population. Without representing the country as a multi-part polygon you have to either apportion the population ...


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R-trees are indeed a great choice. Depending on your platform you might be able to find working implementations so you don't have to go through the pain. A simpler alternative is to use Quadtrees (which are a special case of R-trees, thus simpler) that may be suitable enough for your use case.


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This is an old format, shapefile, personal and file geodatabases are more commonly used today. Note: ESRI never released any specification on this format. The following information is on a best guess (though highly accurate from experience.) The E00 (E01,E02,E03,E0n) is much more that you think from the following Arc/Info Export (E00) Format Analysis: The ...


2

While it isn't specifically addressing examples, the Using Key-Value Stores for Geospatial Data question has a number of examples listed, along with a few ideas about how to implement it for your own needs. This is certainly an emerging area of interest, a few upcoming talks from the FOSS4G conference: GeoCouch: A Spatial Index for CouchDB Geospatial ...


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The answer to this question is subjective, and really it depend on the content your serving up. My experience, one of the main reasons for storing services in different folders is more important when administering security with ArcGIS Server. i.e. A simplistic approach is to have all open services in the root folder, and then services grouped per role in ...


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Not answer but only way to make long comment about test that OP made. Test data Finnish OSM routing table, 379293 lines (allmoust 400k lines) OP had 300k lines. Test machine was highend desktop i7 + 8G ram , database on normal hardisk, database postgresql 9.2 , non default conf. (Table size 118Mb , Index Size 44Mb. Shared memory 2G) select count(*) ...


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Simply export it to MIF file type (MapInfo's human-readable file interchange format). This creates a *.mif and a *.mid file. The .mif is what you need: after the header there's a section that lists the data COLUMNS by name with accompanying data type.


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If you are on Win7 etc, learn to use Recent Places, it will be a benefit for all the software you use. Have your default folder view settings to 'details' with sort by date. Also consider establishing shortcuts in folders or the next level of sophistication, Libraries, which are available from nearly all file dialogs. For instance I have a library ...


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Depending on your needs and data as other posters have touched on it is best to use different methods. If you need a robust and fast application you are best to not use just one data structure but to rather support multiple data structures for different data sets. If you are having trouble understanding how to create an R-tree index and your data isn't crazy ...



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