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When you create child_poverty_by_state, you need to create the geometry table with the following, assuming you are working in WGS84 .. ALTER TABLE child_poverty_by_state ADD COLUMN the_geom geometry(POINT,4326); You also need to ensure that the geometry column has the correct srid, it is not always added from the shape-file, for example for WGS84 ... ...


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You could use ogrinfo which has the possibility to query every supported datasource with normal SQL-sytnax. The supported vector sources are documented here. This would give you the desired attributes. In order to do a comparison with the features stored in the DB it would of course require some scripting or postprocessing. If you don't mind e.g. using ...


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You can build queries by using the Query Builder or an alternative is to use the Expression string builder (Layer Properties > Style > select Rule-based > add a rule > insert your command in the Filter box or click the '...' button to bring up the string builder interface. In both cases, I do not think QGIS supports the comments function when creating ...


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To answer part 1 more directly, you can modify Matej's Field Calculator function to return a boolean indicating whether each record contains more than one alpha character: def has_multi_alpha(fieldName): num_alpha = len([s for s in fieldName if not s.isdigit()]) if num_alpha > 1: return True # or 1 else: return False # or 0 ...


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The below function returns the number of alpha characters in a string: def NumAlhpa(fieldName): return len([s for s in fieldName if not s.isdigit()]) you can easily integrate this into the Field calculator: YourField = NumAlpha( !yourColumnName! )


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ArcGIS Online / ArcGIS.com is a platform/portal which contains a whole bunch of functionality, but it also exposes its feature services via the ArcGIS Server REST API. Log into your ArcGIS Online account then go to My Content and click on the feature service. Under the Layers section, click on the hyperlink - this will take you to the REST endpoint for this ...


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For anybody following this question, I've managed to answer it myself. I had edited all of the code correctly, however, if you wish to do this yourself, you will need to change the privacy setting of your table in cartoDB! I changed it from private to anybody with a link.


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I seems very similar to post "postgis, extrapolate a line". If I avoid repetition of cited post, I think you just need to extrapolate beyond your extreme points. In a query you get something like this should work: SELECT ST_MakeLine(ST_TRANSLATE(a, sin(az1) * len, cos(az1) * len),ST_TRANSLATE(b,sin(az2) * len, cos(az2) * len)) FROM ( SELECT a, b, ...


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Well, others have tried well to answer my question. But those are not according to my requirements. What I did in this case is to handle the case at Server-end. Using PHP array, get the dumped geometries: while ($row = pg_fetch_assoc($rs)) { $result[] = $row['wkt']; } By using above snippet each dumped geometry is stored at an ...


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Alien, That would work for raster as well. In addition, you'll probably want to call the http://postgis.net/docs/manual-2.1/RT_AddRasterConstraints.html SELECT AddRasterConstraints('yournewtable'::name, 'rast'::name); That will ensure all relevant info is properly exposed in raster_columns view.


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The simple way would be to use Select Layer by Attribute to select the focused parcel, then use Select Layer By Location using "share a line segment with the source layer feature" as the spatial selection method, see caption below: This method may then be incorporated into a Model or saved and wrapped around a python script to generate a table export or ...



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