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Questions tagged [postgis-2.0]

Version 2.0 of PostGIS brought a heavy set of new extensions for the PostgreSQL object-relational database, adding greater support for spatial objects.

Check the description of the PostGIS tag here.

446 questions
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How to snap line string start & end vertex to the nearest point?

I have a point layer and a line layer. The points are road junctions, collected using DGPS, while the lines are the connecting roads, collected through Handheld GPS in tracking mode. As a result, the lines are not actually connected to the…
thelastray
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5
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1 answer

nearest neighbor within table using PostGIS

using PostGIS 2.0 and PostgreSQL 9.1 I have a table of photographic observations, sco_photos. The location column contains a PostGIS geometry point specifying where the observation was made. The table is not enormous (about 7,000 rows). I am trying…
Andrew Perrin
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3 answers

How can I export points as GPX?

I have some point data in PostgreSQL / PostGIS. How do I export the data to a GPX file? I looked for commands similar to ST_AsGML and ST_AsKML but could not find anything to convert to GPX (like a ST_AsGPX).
DenaliHardtail
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5
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1 answer

Postgis Difference with Geometry union

I've got two GIS tables, let say A and B. I would like to do the difference of A using B. While it's pretty straightforward to do it with QGIS (using geoprocessing->difference), I've got much more troubles to do it with PostGis. Below a visual…
Arnaud Geotribu
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4
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1 answer

Postgis 2: Polygon/MultiPolygon in a single column

Storing MultiPolygon and Polygon features in a single column used to be as simple as not creating or removing the geometry type check constraint. Is there a similar simple fix in PostGIS 2?
Dylan Hettinger
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4
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4 answers

Importing data with SRID 4269 to GEOGRAPHY type of PostGIS?

In PostGIS, we are importing various US census bureau shapefiles (with SRID = 4269) using shp2pgsql loader. I have medium-sized database with several tables containing fields of type geography (lat/lon points, polygons, multipolygons, etc) that…
GISuser
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3
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1 answer

PostGIS: How to ST_Clip() a raster with a polygon?

I have done: Import a SHP file into PostGIS by PostGIS SHP loader GUI. Import a raster into PostGIS: \raster2pgsql -I -s 4326 landsat.TIF -t 500x500 public.landsat > query.sql After importing all into postGIS, I have tried exporting raster to…
Jackie
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3
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operator does not exist: geometry <#> geometry

I'm running PostGIS 2.0 for PostGreSQL 9.2, and I have a customer who wants to know how close a provided geometry is to the nearest feature in a table. So I'm playing around with the "<->" and "<#>" operators. My problem? The "<#>" operator isn't…
Jeff Dege
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1 answer

Are there strategies for dealing with TopologyException errors in PostGIS 2?

Are there strategies for dealing with TopologyException errors in PostGIS 2? Nearly every function I run against two geometries results in a TopologyException (e.g. ST_Intersection, ST_SymDifference). I always try ST_Buffer(the_geom, 0) first, then…
Dylan Hettinger
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3
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2 answers

Change of geometry type and buffer

I have a layer. I want to transform the type of geometry from point to polygon while creating a buffer around points proportional to the population of cities. I'm testing : ALTER TABLE city ALTER COLUMN points TYPE POLYGON USING ST_buffer…
fcka
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3
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3 answers

Determining if line A is subset of line B in PostGIS?

I have two datasets of linestring features, both of which are from the same source and nearly identical but with minor changes. One of the changes that I need to identify is when one line feature is split into multiple separate features, but with…
wmebane
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3
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5 answers

Loading data using QGIS to PostgreSQL database

I am trying to import a shapefile using desktop QGIS to postgreSQL database using the import shape file to postgresql database tool but it raises the following error: Problem inserting features from file: E:/MOA/sample point…
amsalu
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3
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Loading raster data into postgis database

i would like to add raster data to my postgis database. when i try to check if postGIS is responding to requests using the following command psql -c "SELECT PostGIS_Version()" ,i get an error message saying: psql: FATAL: role '"blessy" does not…
user3401031
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2
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1 answer

PostGIS ST_SummaryStats

I need some help writing the sql for returning the "MEAN" value from a raster(in postgis db) that intersects a defined(inquery) polygon(in postgis db). The polygon layer is called: public.farmpaddocks The raster layer is called: …
Haydlew
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2
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1 answer

Difference between azimuth degrees when i use st_project in postgis

I have two points p1 and p2. SELECT ST_GeomFromText('POINT(92.78488163381019 55.9757874622428)', 4326) as p1, ST_GeomFromText('POINT(92.78482645521103 55.97564239375992)', 4326) as p2 degree between points equal 200.824 and distance…
Vsevolod Avramov
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