Questions tagged [geography-data-type]
geography data type, stores ellipsoidal (round-earth) data, such as GPS latitude and longitude coordinates.
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Calculate surface area of a geography instance using StArea() in T-SQL
In my (Azure SQL Server) database I have stored polygons in the format "MULTIPOLYGON (((longitude1 latitude1, longitude2 latitude2, etc)))".
I want to calculate the total surface area of ...
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Create a new point geometry from origin point geometry, distance and bearing in PostgreSQL
I am trying to create a new point geometry field from this command:
UPDATE cat.datos_parcelas
SET arb_geom = ST_SetSRID(ST_Project(geom, arbdist, radians(arbrumbo)), 32631)::geometry;
-- geom: ...
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Geography type vs Geometry type for PostGIS intersections and other calculations
According to ChatGPT (which obviously could be very wrong) geometry type will always calculate based on Cartesian space even when the CRS is 4326 coordinates, whereas geography type will calculate ...
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ST_intersects returns different result for Geometry params vs Geography params
ST_Intersects returns true for geography parameters but it returns false for geometry params:
Following is the query for geometry params and it returns true which is incorrect.
select ST_Intersects (...
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Geometry comparisons in SQL
Newbie to GIS here.
Equality can be defined on a geographic value by seeing if they have a collection of the same points. For example, something like:
-- The equality
-- `LINESTRING(1 1, 2 2) = ...
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PostGIS ST_Relate reports polygons intersect but Google Maps says otherwise
I'm creating a Geography database that does not allow polygons to overlap/intersect (having positive common area that is). The user interaction flow is:
User creates and exports a KML document from ...
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Converting Geometry to a Geography yields an invalid shape SQL SERVER
I have two Geometry shapes of types Polygon or MultiPolygon [with Lat & Lng points] that I want to get their intersected shape.
I do this as follows:
land_shape.STIntersection(grid_shape) as shape
...
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ST_Covers(envelope, point) yields different results for same point
Clearly missing a basic concept. Using ST_Covers, I'm getting "true" for a geography point that clearly exists outside of the polygon. Looking at a number of points, it appears latitudes are ...
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Google Earth Engine update band values of aggregated image to just the values depicted in brackets in the band when data type is double
I am trying to aggregate the hansen forest loss data from a 30 x 30 m resoltuion to 1 km x 1 km resolution, where the value of the band is the proportion of the cell coverage. I feel like I am close ...
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geometry vs geography for distance measurement and large dataset
I'm working on a project where I have clusters of GPS coordinates to store, let's say ~20k points per cluster. The clusters overlay with big cities, like London or New York. I have many clusters ...
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converting geometry of SRID 0 to geography
My geometry columns have SRID of 0. Can I simply convert them to geography as such:
routes.geom::geography <-> pc.geom::geography as distance
in order to get "distance" in metres?
P.S -...
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Unexpected ST_DWithin result when using geography [closed]
This query:
SELECT ST_DWithin(
ST_Buffer('SRID=4326;LINESTRING(7.1670005 45.9968257,7.1670216 45.9969537,7.1670216 45.9971326, 7.1670484 45.9972789, 7.1671905 45.9974074, 7.1672844 45.9974801, 7....
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Efficient way to "gridify" SQLGeography shape
Read the "Background" below for full details of why I want to achieve this.
Given a shape, I would like to process it in such a way that it conforms to a 0.00001 x 0.00001 degree grid. (This ...
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SQL Server STIntersects, STDistance and STCointains with Lat Lon points and Geometry Polygons [closed]
I need to create 3 functions in SQL Server (2017) that has to do the following:
IsPointInsideTown(Point, TownCode, [SRID]) -> true/false: indicates if the point is inside the town's polygon.
...
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ogr2ogr cannot import into table with two geography columns
I am using ogr2ogr to import geojson files into a PostGIS table. The table has two geography columns ("footprint" and "centroid"). The geojson files contain polygon features, and I ...
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