PostGIS is an extension for the PostgreSQL object-relational database that adds support for geographic objects.

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mulitlinestring to linestring

I am using postgres with postgis and I have a set of points which I would like to interpolate with a set of lines. Now my problem is that the set of lines are of type multilinestring. Is there a ...
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1answer
227 views

Howto setup osm2psql

I'm following these instructions to setup osm2psql . I need it to import osm data file inside a PostGIS DB. The following steps worked fine: createdb -E UTF8 -O user mydb createlang plpgsql mydb I ...
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2answers
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PostGIS raster value of a lat/lon point

I have a tiff raster in my PostGIS 2.0 database. I want to get the value of the raster at a specified lat/lon point. I have: postgresql-9.1 postgis-2.0-svn with raster support a raster imported ...
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1answer
317 views

Join based on maximum overlap in PostGIS/PostGresQL?

I have two sets of polygons in two tables. The sets overlap each other. For each polygon in set A, I would like to get the ID of the polygon in set B that it overlaps the most. I'm using PostgreSQL ...
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5answers
4k views

How to load Shapefiles into a remote PostGIS db using command line?

Can we import a Shapefile from a system which doesn't have PostgreSQL installed (client machine) into a system having PostGIS installed? I am getting problem with 'shp2pgsql' and 'psql' since both ...
6
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2answers
329 views

Clarification of the “25D” option in ogr2ogr

[EDIT: In my original post, I had received an error that was based on a typo, so I scrapped that part of the question, but left the questions that still apply.] In the ogr2ogr docs it says: -nlt ...
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1answer
861 views

QGIS WKT Raster Plugin error, what does this mean?

I have been playing with the WKT Raster plugin. I have installed the WKT Raster experimental binaries in PostGIS successfully and followed the instructions in the read me to the letter. When i am in ...
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1answer
174 views

How to achieve equivalent to Dissolve from ArcGIS for Desktop using ST_Union?

I am trying to achieve an equivalent to the Dissolve tool from ArcGIS for Desktop using ST_Union from PostGIS but it seems I am not getting expected result. I have one table which has certain ...
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1answer
360 views

How to interpolate polyline or line from points?

We have a lot of points, but with no timestamps to create ways. For now, I've created a sample of the way the points traverse. It's in here, this way can be compared with a Google one. I haven't ...
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1answer
857 views

Why do TIF loaded into PostGIS lose their colormap?

I have successfully loaded a TIF image (using raster2pgsql) into my PostGIS 2.0.1 database. I can load the raster image into QGIS and it displays in the correct space. However, it has lost all colour ...
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3answers
3k views

Bounding box for PostGIS table

Is there an easy way to get the bounding box for an entire table in PostGIS? Thanks
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328 views

How to filter points based on proximity while inserting into PostGIS?

I have a large amount of locations that need to be inserted to a PostGIS database. However, I'd like to aggregate these points so that if there's already a location, say nearer than a kilometer, then ...
5
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1answer
635 views

How to get GeoNetwork to search through PostGIS fields via GeoServer WMS

I can't seem to get GeoNetwork to search through my PostGIS fields via GeoServer WMS. According to the GeoNetwork Documentation: it should loop over datasets served by the service and produce ...
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4answers
2k views

How to convert multipoint layer to point

I have a Spatialite layer which is multipoint (following a QGIS Save As from shapefile). I need it to be PostGIS and POINT. I have tried ogr2ogr -nlt POINT and got 'new row for relation "xxx" violates ...
4
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1answer
81 views

Why does only one of the following queries throw an error?

There are 2 SQL queries: SELECT wkb_geometry FROM building_polygon WHERE ST_Contains(wkb_geometry, ST_GeomFromText('POINT (29.4 60.1)')); SELECT wkb_geometry FROM building_polygon WHERE ...
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2answers
421 views

QGIS saving analysis output as Postgis table

i am using QGIS and Postgis together. I can load data in Postgis and than i import it to QGIS. But i am trying to save an analysis output (example: buffer analysis, voronoi polygon or SEXTANTE ...
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2answers
257 views

How to find out what features /tags are included in an .osm or .pbf file?

I would like to load osm data into a postgis (postgresql) database. In How to load OSM data into PostGIS preserving all Tags? there has been a solution posted: Download the OSM files (in .osm ...
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2answers
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How to select segment of linestring using PostGIS?

i have PostgreSQL+PostGIS. I have a linestring: "LINESTRING(60.7014631515719 56.8441322356241,60.7023117507097 56.8445673405349,60.702948200063 56.8447993944193,60.703902874093 ...
4
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1answer
197 views

Update PostGIS after updating GDAL?

I am using PostGIS 2.0 and I want to use the raster functionality through mapserver. It seems as if the latest official GDAL release 1.9.1 has an unstable PostGIS raster driver, as pointed out in a ...
4
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1answer
808 views

Raster data on PostGIS

I need to publish raster and vector data through GeoServer WMS service and I have already chosen PostGIS as datasource to keep vector data. Now I would like to know what is the best practice to work ...
4
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1answer
317 views

Self-intersecting polygon using extreme values

I have this polygon POLYGON((1.2E-15 1.1E-15,1.31E-15 1.21E-15,-180 -90,180 90,1.2E-15 1.1E-15)) It uses an extreme coordinates like (1.2E-15 1.1E-15) and (180 90) When I call ST_isValidReason, ...
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1answer
2k views

Performing Geoprocessing SQL Queries in QGIS from a PostGIS Database

This may be a dumb question, but is there way to run a PostGIS geoprocessing SQL query in QGIS? Specifically, I am thinking of running SQLs such as ST_Union, ST_Split etc etc. I have tried the ...
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4answers
1k views

OSM To Postgis & WGS84 problems

I’m trying to import OpenStreetMap (OSM) data into postGIS it doesn’t appear to be working in that features do not appear to be in the correct place.. Using the QGIS OSM add in and a coastal shape ...
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622 views

Indian Latitude Longitude values

I am in need of around 10000 and odd Indian latitude and longitude values for my openlayers project. I have to load them in a postgis db. so a sql file or atleast text file would be better than a ...
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2answers
198 views

How can I GROUP BY linear spatial clusters with PostGIS?

I have a series of points in a horizontal line, arranged into discrete spatial clusters by the underlying data pattern. Here's an example of what they look like: How can I use PostGIS to group them ...
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3answers
248 views

Best choice for building static maps: PostGIS, SpatiaLite or Shapefile?

I usually build static topographic maps, which are mostly printed. I'm often using OSM and rasterfiles (mainly different DEMs). The areas I'm mapping seldom exceeds 20.000 km². I'm using exclusively ...
3
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1answer
100 views

How to transform a set of street-segments into city-blocks, with PostGIS2?

Theoretically is possible to obtain the polygons of city blocks (urban blocks) from streets, when streets are represented by street axis (LineStrings). The urban blocks are bounded by streets, so ...
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2answers
222 views

QGIS DB manager Import layer/file tool won't allow me to choose “Append data to table”

I want to append some data to a layer in my PostGIS DB using a shapefile, but when I use the Import layer/file tool in QGIS, it doesn't allow me to choose the append option. Why is this and how do I ...
3
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3answers
445 views

Create a point x meters from origin using st_translate in postgis

How do I create a point 1000 meters away from a reference point? The ST_Translate only supports geometry type. I also tried using ST_GeomFromText but that returns a unit and not in meters. Here is ...
3
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1answer
688 views

How to save a newly created shapefile in PostGIS?

I am creating shapefile using shapefile.py and my database has records more that 65k which is the limit of the shapefile. How can I create shapefiles then? Is it possible that somehow I am able to ...
3
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1answer
2k views

How to filter features in a layer?

I am trying to display certain features in a shapefile-based layer using QGIS. I have found the subset function in the properties panel, which does exactly what i want, but is too tedious given that I ...
3
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1answer
2k views

How to get the coordinate system from a PostGIS database?

My question is probably amazinlgy stupid, but I can't find the answer myself. I would like to extract from a database the latitude and longitude of points. For now, I'm getting x(the_geom) and ...
2
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1answer
86 views

Using PostGIS functions in ArcGIS Desktop for Layer Definition Query?

I am connecting ArcGIS Desktop 10.2 to Postgis 2.0.3 with PostgreSQL 9.2.4. No SDE. I can load data with no problems and access the data in ArcMap. However I can't seem to use PostGIS functions within ...
2
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1answer
166 views

PostgreSQL : finding all lines intersecting with a polygon

I am totally new in the world of GIS but as a student surveyor I am working on a project using postgreSQL and PostGIS. I have one database with all the roads of my country (lines), and one database ...
2
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1answer
71 views

When would a PostGIS geometry compare using ~= return true when ST_Equals returns false?

I have a couple of featureclasses in a 10.2 geodatabase/PostgreSQL 9.2.2 database and I've been struggling with the FeatureCompare tool--it is telling me geometries are different on some features ...
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1answer
57 views

PostGIS: How to understand ST_RasterToWorldCoord() right? (PostGIS 2.0)

After putting raster in to postGIS by this Thank @Sorin for helping me out! Now, I want to output raster tile, then view it on QGIS. But the problem is the output of ST_RasterToWorldCoord(raster ...
2
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2answers
285 views

What's the fastest way to do a bounding box query in PostGIS

I have a Postgres table, with almost 2 million rows, with a long-lat coordinates field in the form POINT(-73.4938 33.2405). Supposing there's a geospatial index on that field, what's the most ...
2
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1answer
88 views

How to change table name of command raster2pgsql

I am completely newbie with GIS and PostGIS as well I'm trying to load raster into postgreSQL with raster2pgsql. It runs well. However, the table name of the raster is generated automatically. For ...
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2answers
2k views

Installing postgis on postgresql 9.1 not working

I'm trying to install Postgis 2.0 on a perfectly functionig postgresql 9.1.10 database. I installed the package via: richard@srv1:/$ sudo apt-get install postgresql-9.1-postgis postgis Reading ...
2
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1answer
202 views

GeoWebCache seed task dies immediately after being submitted

The data comes from Geofabrik's Brazil slice: http://download.geofabrik.de/south-america/brazil.html Imported into a PostGIS DB with osm2pgsql. GeoServer is 2.4.0, running on latest Tomcat 7.0.x, on ...
2
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1answer
588 views

GeoTools and PostGIS with ESPG:3857

I'm trying to use both PostGIS and GeoTools with the same ESPG:3857 projection, however, it looks like the projections in PostGIS and GeoTools differ. This is what I have in PostGIS: PROJCS["WGS 84 ...
2
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1answer
663 views

PostGIS Dissolve/Union close polygons

I have approximately 1 million polygons that have been split by lines. However, this has caused one half of a polygon to be separated by approximately 50cm from its other half. After doing a lot of ...
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1answer
240 views

How to merge connected lines with same direction (PostGis)

I am looking for a way to join all lines that are connected, have the same direction, i.e. start point of one is end point of the other, and share some common attributes. In fact, I want to connect ...
2
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2answers
277 views

Can Geoserver return the raster value of a lat/lon point

I have a GeoTIFF published by Geoserver 2.2 and being used by Leaflet via WMS. How can I get Geoserver to return the raster value at a lat/long point? I'm guessing it has to do with using WCS, but ...
2
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1answer
266 views

Unreachable vertex

I'm developing an application for academic purposes that mainly gives to the user a recommended itinerary for a previously introduced preferences (Gastronomy, Leisure,etc.). For this purpose, I use ...
2
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2answers
1k views

KML from EPSG:4326 to EPSG:900913

im trying to create KML files manually (XML format) by extracting data from a postGIS database with "geography" values in a column. But i belive i need to transform the projection of each row in the ...
2
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1answer
741 views

How can I fix QGIS PostGIS Manager error 'shp2pgsql' is not recognized?

I have QGIS 1.8.0 installed via OSGeo Installer and work on win 7. All I need is to upload the shapefile to the database via this plugin. Unfortunately I am receiving an error: Something's wrong: ...
2
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0answers
225 views

From pgRouting shortest_path back to osm node id

I'm successfully performing path finding queries like shortest_path on data imported with osm2pgrouting. The tables I have inside my pgrouting DB are the following: List of relations ...
2
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1answer
359 views

Querying PostGIS Raster with MultiPoint

For one of my projects using PostGIS 2 I have a table with GPS tracks (igc_files). It holds records including a MULTIPOINT() column that has about 1,000 points for each record and a column that has an ...
2
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1answer
812 views

How to find polygons inside polygon with PostGIS 2.0

I have a relation representing all the counties in my country and the other one containing all the districts - e. g. each and every county is composed of several districts. How do I select them with ...