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15

I've described the process of installing and spatially enabling an sqlite db here: SpatiaLite Quick Start. Basically, you need to get init_spatialite-2.3.sql and run it on your db. You can then create point geometries using this function: MakePoint( x Double precision , y Double precision , [ , SRID Integer] ) : Geometry


8

You have two tasks: (a) find the grid data for the vertices of a grid cell in which a GPS location (x,y) lies and (b) interpolate those data. An efficient way to accomplish (a) is to store the grid as an array with a single index. Often grids are stored by rows with data progressing left to right within each row. A grid is determined by the coordinates of ...


8

In the documentation, it is alluded to that you cannot edit data in a SQLite database from ArcMap: You can connect from ArcGIS to an SQLite database to create maps and perform spatial analysis on your data. However, the only place this appears to be explicitly stated by Esri is in the ArcGIS Discussion Forum: Yes; you cannot edit data in a SQLite ...


7

I don't know if this is the answer you want, as it's not a point and click answer, but this is how I would do it probably. In Spatialite, add a new geometry column. Assuming you want WGS84 (lat/lon) AddGeometryColumn( yourTableName , geometryColumnName, 4326, 'POINT', 'XY') Then create the geometry from WKT generated from the X/Y coordinates update ...


7

For sake of posterity, the short answer is that MapInfo and FDO (AutoDesk technology) are far removed from any development with SQLite, compared to the members of the SQLite Consortium. MapInfo and FDO (AutoDesk) would be contributing binary to their downstream users, via their products and services. Spatialite is specked under a triumvirate of ...


7

You can connect to Spatialite via Python using the latest version of pysqlite instead of pyspatialite. Spatialite is just the spatial enablement of SQLite so this works, but if you are connecting in this way (via pysqlite) you need to load the libspatialite extension to be able to use the spatial functionality of Spatialite. from pysqlite2 import dbapi as ...


6

In SQLite, and thus also in SpatiaLite, there's no date type per se. See Datatypes In SQLite. When a string column is saved in the format "YYYY-MM-DD" then you can apply some date functions to it, such as strftime() to get the date formatted in other ways. However, if you've saved your dates in any other way, they are NOT recognized as dates. What I would ...


5

The sqlite file from NE is in FDO-OGR format, not the native spatialite geometry. If you're willing to do some manual labor, here's a way to convert to a spatialite db: First make a new, empty spatialite database (I call it "nev.sqlite"), then in a separate terminal session open the original natural_earth_vector.sqlite with spatialite. (I used the newer ...


4

I found the solution as for source table did not created with spatialite option which default is false. To do that simply add parameter to ogr2ogr utility -dsco "SPATIALITE=YES" then all SpatialLite parameters shall work as requested.


4

You can install the Open Source ArcGIS OGR Workspace plugin from AmigoCloud that will give ArcMap read access to spatialite and a whole bunch of other formats. It is free. Let me know if you want to test the binaries - I already have some people doing that with success. They only work with 10.1 at the moment since that is the only ArcGIS version I have ...


4

ogr2ogr? See here for more information and maybe here as well Cheers St├ęphane


4

Have you tried something like [1]: spatialite test.sqlite 'CREATE VIRTUAL TABLE "roads_net" USING VirtualNetwork("roads_net_data")'. And the correct routing query seems to be [2]: SELECT * FROM Roads_net WHERE NodeFrom = 1 AND NodeTo = 512; [1] ...


4

Here's something you might try: You can create buffers around all the points at a "reasonable" distance that you choose based on the clustering. Then merge the circular buffers together. That should give you polygons enclosing the clusters of points. In spatialite you would do: Create a polygon table for the buffers and a second one for the merged circles: ...


3

Have you had a look at OpenLayer's "Dynamic POIs via a Text Layer" example? That should be even easier than an SQLite solution. Update: Geodjango doesn't seem to be an option on shared hosting. See GoDaddy Forum: You can install and use Python and FastCGI on our Deluxe and Premium Linux shared hosting accounts. However, Django will not function on ...


3

You can use GeoDjango on a shared server at http://www.alwaysdata.com (just check the features list and the prices: http://www.alwaysdata.com/plans/shared ) They have VERY competitive prices and you can even test the env for free. They do the PostGIS configuration on their side and the installation of geoDjango so that you don't have to configure ...


3

This seems to be a bug (see http://hub.qgis.org/issues/9628 - apparently fixed in 2.2.) Possible workaround: I have experienced that when using fields from joined tables (I have tested dbf and csv), the field calculator messes things up when I choose "Create new field". If I change to "Update existing field", things seem to work.


3

In native (out of the box) Python installations extensions are disabled within sqlite3. Unfortunately this means that you will need to build the base pysqlite2 library manually and use that instead. On Windows this will mean that you need a C compiler (Visual Studio comes with one - I've used Visual Studio 2010 for this before). However (with massive props) ...


3

Standard OSM tiles are in Spherical Mercator (SRID=3857) so it will probably be easiest to build your grid using the same projection. If you use SM, you might store the data at the highest zoom level OSM supports, or at the highest level zoom level you'll permit users to zoom into. If coverage is sparse, use a data structure along the lines of XIndex, ...


3

The value stored in a cell from a heatmap is often normalized by its area. In this case I would rather suggest an equal area projection so that you can easily aggregate to larger scale


3

From the ogr2ogr docs, use the -nln name option to assign an alternate name to the new layer.


2

I appreciate the input of everyone here. A number of the comments triggered thoughts and I figured out a solution. Many thanks to underdark for her comments, as they gave me some avenues to pursue. I figured out how to install FeatureServer on a GoDaddy hosted website. Much credit goes to the FeatureServer Getting Started document. From GoDaddy: If ...


2

You should be able to go directly from .tab to spatialite using OGR. See the spatialite format page for more details. You also don't have to create multiple dbs and merge them, just 'append' them all together from the start.


2

Since QGIS can read OGR layers, try using OGR's Virtual Format: http://gdal.org/ogr/drv_vrt.html . Create a text file with the following content and open it as vector layer in QGIS (Layer -> Add Vector Layer). Just replace the table name as well as the latitude and longitude column names according to your database table. It's recommended to store the file ...


2

Use the spatialite_osm_raw tool for importing OSM files (raw format tables, strictly corresponding to XML "Also this tool is intended to parse a whole OSM dataset, thus creating the corresponding SpatiaLite's DB-file; but in this case the generated DB-file will adopt a completely different data layout than in the previous scenario. In this case will be ...


2

My understanding is that to do this using ArcGIS Desktop 9.3 (or 10 or 10.1) the simplest, but expensive, option would be to use the Data Interoperability extension. However, using ArcGIS for Desktop 10.2 with no extensions ... You can connect from ArcGIS to an SQLite database to create maps and perform spatial analysis on your data. You connect ...


2

Your MS Vs SQLLite code is different on the join: MS: FROM Inspections INNER JOIN Sections ON Inspections.GISLink = Sections.GISLink; SQLite: FROM 'Inspections', 'Sections' inner join 'Inspections' on 'Inspections'.'GISLink' = 'Sections'.'GISLink' You SQLite query is joining Inspections onto itself


2

It's not %s in your SQL prepared statements, it's ?. statement = "INSERT INTO %s (%s) VALUES (?, ?, ?);" % (table,columns) Also, you can define statement far earlier in your code (before the walk) and just reuse it.


2

I'm not sure this is really the place for basic SQL, but I guess it is loosely related to GIS.... This is pretty basic stuff, you really need to read about SQL if you're trying to do anything in GIS with it: update yourtable set tilenumber = replace(index,'_','') I would start with the basics of SQL itself (e.g http://sqlzoo.net/ and then move onto the ...


2

Also, in order to use spatialite style queries, you must specify -dialect sqlite in ogr2ogr and ogrinfo sql



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