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10

We are currently working on a complete redesign of our geodatastores. I have to say that their evolution took more than 20 years till now. We identified the following key features in geospatial data management: simultaneous editing permissions to read or write portions of data hot update while running services that rely on data (Transactions and ACID ...


7

I don't know if it still works, but a couple of years ago I hacked together a method for downloading the US Seamless National Elevation Dataset in bulk that might work for topo raster maps too. To bypass the map viewer put the coords on the URL like so: ...


6

Generally when an organisation says that their data may not be used commercially they really mean that it cannot be used commercially without payment for some type of licence. ESA will probably have bought a licence from eurostat that allows them to publish and make available product CONSTRUCTED FROM the eurostat data BUT NOT CONTAINING ALL THE ORIGINAL ...


6

If you'd like to see if the OSM data would suit your company's needs, download a test area from WeoGeo: http://market.weogeo.com/datasets/osm-openstreetmap-planet You can select just the 'Boundary' layer and a desired AOI and go from there. Be aware of OSM's attribution rules if you do decide to go with the OSM data ...


5

There is always geonames though I have no idea how comprehensive their South Africa data is. Another option might be the South African Statistics agency


5

What about the FREE 24K geotiff DRGs available through the Libre Map Project? All 24K DRGs for all 50 states are available there. They are collared, but I had access to GlobalMapper, which has a nice function that removes collars easily (and surely there are other ways to deal with those). They are filed nicely on the server at the Internet Archive and the ...


5

I put a list online a while back of a number of free GIS datasets (see http://freegisdata.rtwilson.com/). Two that may be relevant to you are: Natural Earth populated places - although this is likely to only have fairly large places in it (available at http://www.naturalearthdata.com/downloads/10m-cultural-vectors/) NGIS Country Geoname Files - a list of ...


5

When you publish any type of service, you publish from a specific database connection, which points to a specific version of the database. So, create a new database connection to the specific version that you would like to publish the geodata service from, then either add the data to a mxd and publish from there, or right-click on the version database ...


5

I'd suggest to have a look at TomTom offer. I've used their MultiNet product. This dataset is mainly developed with navigation in mind, but some of the layers provided cover administrative division and zip code areas. At least 10 levels of Administrative Orders are defined for each country. The highest level, Order 0, is always the Country, which is ...


4

There is also the Global Administrative Unit Layers (GAUL) from FAO , same has the GADM data (there is somehow a permission that can be requested). Another source you can look at are the GIS Data Vendors from GPS companies: navteq tele atlas They use that kind of data as well, but I am not sure if they can sell it back to you and also the price they ...


4

If you are interested in OSM then yes it is quite possible, I will suggest first download the Osm planet file. Then extract only the administrative areas by using Osmfilter and write subset of planet file which includes only administrative areas. After this use QGIS or Arcgis to extract administrative areas. This whole process needs some time so before ...


3

MapIT have South African Datasets including Towns/Cities (POI) - It is usually derived from TeleAtlas (Owned by TomTom) so likely to be costly. http://www.map-it.co.za/about/index.html From the Press Release: June 2011 "Given these trends, MapIT, Southern Africa’s leading enabler of technological mapping solutions, is concentrating on supplying accurate, ...


3

I found OpenStreetMap to have GREAT amount of sets of data for ZA. Although some parts are more populated than others, compared to Google. You can Export the data to XML file from OSM, and then extract the POI's - this is a lot of work, but its free. Statistics SA and various government departments work with SHP files. (hard to get your hands on) - try and ...


3

You find a dowload here : http://arnulf.us/PLZ However, the data is from 1999 and I'm not sure if it still is up-to-date.


3

Quality control checking in GIS falls under two main categories, geometric and tabular. Since GIS workflows are not standard your QA/QC process is unique to your case. Geometric In general most proprietary and open source GIS applications have a set of tools that check for geometric errors (e.g. ArcGIS Checking and Repairing Geometries, QGIS Check ...


2

Try the office of the Surveyor General as well. They have a wealth of information, much of which they provide at no charge: http://www.ngi.gov.za/itisportalinternet/ There is also free spatial data available from DIVA-GIS: http://www.diva-gis.org/Data


2

In place of feature class I would use Spatial Dataset in Vector Format initially, and then shorten to Vector Dataset. I think layer can be considered to be an already vendor independent term.


2

There is only one way to efficiently do this that I know of. Load the replica database fields into a dictionary using a searchcursor with the GlobalID as the dictionary key, then loop through a searchcursor on the origin database and attempt to retrieve the GlobalID dictionary key that matches each record. Set up four counters: count, added, deleted, and ...


1

This is rather old (1994) so predates RDF/OWL by a long way, but may be of theoretical interest. It was developed independently from, but around the same time as, Geographic Markup Language (GML), and is more of a conceptual discussion than a comprehensive catalog. Towards a geographic semantic database model, by M Feuchtwanger (me). Here's the abstract: ...


1

Currently, you can use any encoding in Shapefiles and the most common is Unicode. (and OpenStreeMap data use Unicode) I have no problem to open the Moscow shapefiles in QGIS and the Cyrillic characters appears: If you look at the properties of the layer, you can see that the encoding is 'UTF-8' (Unicode) -> you know the encoding of your shapefile and ...


1

I'm not sure about your exact workflow, so I'll try to give a general answer. There are two different ways that geodata can be used, and the answer depends on which one you need: You are showing the data on a map. In this case, if you load 1000+ vertices as graphics on the map, you will have a low performance. What you need to do is to load the data as a ...


1

Geofabrik's free download server. This server has data extracts from the OpenStreetMap project which are normally updated every day. So that its better to collect world boundary following link, If its suitable for your company you can use this link. http://download.geofabrik.de/


1

I've found the best and most reliable source for South African GIS data is from Planet GIS. Their complete data sets for South Africa can be found here, but the two most useful ones are: Administrative boundaries: this covers the provincial, district, local municipality and ward boundaries. Places of South Africa: this covers fine detail down to the suburb ...



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