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

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How to add constraints in PostGIS?

I have table that containing road network. Table structure is CREATE TABLE final_all_india_road_network ( gid serial NOT NULL, "name" character varying(254), code character varying(254), ...
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How to view error feedback in qgis when testing connection to postgres database?

Using qgis 1.8 on Ubuntu 10.04 with Postgres 8.4.13 I am creating a new (and my first) Postgresql connection in qgis. I can connect to the user and the db using the pgsql client. ...
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How can I get the geometry length in meters?

The ST_length() function returns the length of a linestring but not in meters. Is there a function like ST_Length() but in meters?.
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How to create a network with all the track points

I have created a sample network through the use of gps visualizer. Than I used the ogr2ogr function to import this data in my database. Now I have a table which holds all the track points of these ...
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278 views

Is it possible to change the projection used in OSM2PO?

Is it possible to change the projection used in OSM2PO? I used the following command to generate a SQL file which I loaded into my database: java -jar osm2po-core-4.2.30-signed.jar prefix=at ...
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994 views

Creating proper GeoJSON from PostGIS data using node.js

I am trying to build a GeoJSON object from a SQL query to some GIS point data in a postgis postgresql database. A snippet of my node.js app.js is below. As it stands I understand building the type ...
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219 views

PostGIS Implementation of Brabyn and Skelly Road Network Travel Time Model

Is there a PostGIS implementation of the Brabyn and Skelly road network travel time model for the New Zealand road network? This model is outlined in: Brabyn L, Skelly C. Modeling population access ...
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325 views

How to get all attributes from a non geometry PostGIS layer with Python in QGIS?

I want to extract all attributes from a non geomety layer in QGIS with Python, but there is only the function uniqueValues(fieldIndex) More specific: I have a postgresql table which is loaded into ...
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How to view a 155 MB raster stored in PostGIS?

I am using the following command to load a raster into a postgres database: raster2pgsql -I -C -e -Y -F -s 3086 -I -C -M myraster.tif myraster -F -t 30x30 | psql -U postgres -d database -h localhost ...
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178 views

Finding the Geometry within which a Point falls

I have the following query, which takes on average about 4 seconds. How might one improve the query such that the same response comes back faster? SELECT * FROM geometries g ORDER BY ...
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Clarification of Logical Operators in a PostGIS Database

The following query returns this result: select count(*) from a , b where a.geom && b.geom; count ------- 66514 On a postgis 2 database. What does the logical operator AND ...
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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 ...
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262 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 ...
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Speed differences between SQL Server 2012 and PostGIS UnionAggregate

There seems to be a massive difference in speed between PostGIS and SQL Server 2012 with a union aggregate function. SELECT geometry::UnionAggregate(the_geom) FROM loc GROUP BY LocalityCo vs ...
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238 views

PostGIS raster support

I have the following requirements to manage raster data 1) Convert raster-maps from BSB format to PNG or GeoTIFF 2) Cut the borders of the map 3) Merge individual maps to form a contiguous coverage ...
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969 views

Access PostGIS Raster layer through mapserver

I am trying to use a cgi script calling mapserver to display a raster layer that is stored in a PostGIS database. However, only a blank white image is returned and I don't know where the problem is. ...
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378 views

Open-source software for managing terabytes of different formats of geospatial data?

I have a problem that I am sure many GIS Teams or Departments have which is how to find, keep track of and manage multiple different datasets from multiple sources. I have read the responses from a ...
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Editing layers in GeoServer with web application

I wanted to edit layers in GeoServer where they are store in PostGIS database. I have refereed ...
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How to split OSM roads into individual segments at intersections?

I want to create a road-network for use with pgRouting using OpenStreetMap data. I loaded a shapefile from GeoFabrik into a Postgres table (with PostGIS enabled). However, one problem I had was that ...
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How to specify gdal_contour output format as postgresql table?

I want to generate contours with gdal_contour command. It generates an output as shapefile by default. I want this utility to output a postgresql (postgis) table. The documentation says there is a -f ...
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How to change the SRID of exisisting data in PostGIS?

While importing my shapefile data to PostGIS, I did not select the proper Projection. How do I now change the SRID of the data, without transforming the Coordinates?
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How can I transfer data from one PostGIS database to another?

I have quite a bit of GIS data in a old PostGIS Database (version "1.1.6") and I need to transfer it to another PostGIS Database ("POSTGIS="1.5.3"). I tried creating a backup and restoring that on ...
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618 views

Create WMS service from existing image tiles

I have image tiles (jpg image files with txt georeference info files; see picture) stored in catalog (about 12GB, size one image tile ~ 275*466 meters). It possible create WMS service of the tiles to ...
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How to install shp2pgsql-gui on Mac OSX Snow Leopard?

I am getting started with PostGIS. I am trying to understand how to install the plugin shp2pgsql-gui under Mac. Right now my 'Plugins' tab in pgAdminIII is blank... Thanks!
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Displaying text from dxf in Openlayers

I managed to import .dxf into Postgis table, and now have, among others, rows with Point geometries and values in text column (which corespodent with Label values from ACAD .dxf). What is the best ...
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searching GeoJSON features

After googling for many days and reading the OL documentation, I don't understand well how the filterToParams in OpenLayers.HTTP protocol should work, what I'm trying to do is to find and display the ...
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Why won't this PostGIS query display in QGIS

I am having trouble rendering the following PostGIS query in qgis1.803. SELECT s.musym, st_intersection(s.the_geom,f.the_geom) as geo, nextval('"soilsplittersequence"'::regclass) as k From ...
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326 views

How to reproduce Stamen's Toner PostGIS setup?

I'm trying to render Stamen's toner map with Landez which uses Mapnik. The style I'm rendering is from Stamen's toner project. I'm using the one which only renders labels (no lines). I imported the ...
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How do you treat partial 3d features in PostGIS?

We have features from survey data that contain partial 3d information. The most common example would be a 2D LineString representing a road, that contains elevation information in certain points ...
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st_intersection; What Im doing wrong?

Im trying to run this query : create TABLE data.agri_grc as select id, code_00, ST_Intersection(data.agri.geom,data.grc_bor.geom) as geom from data.agri; But im getting this error: ERROR: missing ...
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262 views

Problem with Pgrouting 1.5

Hi all and thanks in advance. I have Postgis 2.0.1 and PgRouting latest version. I'm using osm2pgrouting to import OpenStreetMap data everything goes ok the trouble is that I always get source and ...
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87 views

Update table using contains function

I have a table that containing placename regions and another table of roads. I have another table that containing centroid of both placename region and roads.The table structure of third table is ...
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How to take polygon centroid in Postgis

I have table with column name,Latitude and Longitude.I want to update this with polygon name and its centroid latitude longitude.I know there is a function in postgis st_centroid(geometry). But I want ...
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Is it possible to geocode street intersections using Nominatim?

Is it possible to geocode the location of a street intersection using Nominatim? Example geocode query Commonwealth Ave at Washington Street, Boston, MA Successful Geocode by Google ...
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Calculating from a location to another location (calculation must be on a line/road path)

I'm using QGIS. I'm new. I have a CSV file, with the source point (the_geom) and destination point (the_geom). I have a road network already imported into PostGIS with pgRouting, and I need to have ...
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How you can repair invalid topology errors within postgis?

I've imported the shapefile of corine land cover project to my postgis database and the select gid, ST_IsValidReason(geom) from gis.clc2000 where not ST_IsValid(geom); returns in every occasion ...
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How to export data from QGIS to display in Google Maps?

I'm exporting layers of a project for a quantum gis postgis table and visualizing the data in gmaps, but the coordinates are very wrong. is there any special way to export the quantum gis? postgres ...
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Postgis error on select all intersetcs of a polygon [closed]

i can get all polygon on intersects this:-7.9245860488441 -37.122384500713,-7.9245860488441 -37.11904223938,-7.9233955716106 -37.1187601948 SELECT * FROM propriedades WHERE ST_Intersects( ...
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401 views

How can I find the nearest points (plural) on a line segment using PostGIS

I'm locating the nearest point on a line segment with PostGIS and ST_ClosestPoint, I can select the point on each of these line segments which is closest to the starting point. Which looks something ...
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Database has duplicate values after running pgrouting

I am a newbie with postgresql and sql statements so maybe it is a trivial question, I'm sorry for that. I am working on a postgis database and try to use the pgrouting function. My goal is to store ...
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Is there a paid service for accessing a PostGIS/OSM DB

I want to render a world map with mapnik and postgis, but do not want to set up my own DB, because the needed hardware and processing time for the OSM import make it nearly impossible for me. I just ...
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1answer
150 views

Proximity query approach

Let's say that I have two tables in PostGIS, tracks and cities, each table has two columns, in both cases the columns are called name and way, name is a string, way is a geometry. I want to retrieve ...
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Finding center point of MULTILINESTRING using PostGIS?

How to find the center point of MULTILINESTRING, which lies on the multiline? I am using SQL in PostGIS
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435 views

I wanted a tutorial link to start with geoserver and Postgis for ASP.NET

I wanted a reference material for coding using C# in ASP.net with geoserver and Postgis. Please tell me reference material for the same. I have searched for several reference material but did not ...
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752 views

PostGIS Out of Memory during bulk insert

I am attempting to import OSM road data using an SQL file generated by OSM2PO. However I keep getting the following error: ERROR: out of memory SQL state: 53200 Detail: Failed on request ...
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For the non-IT savvy GIS person (not great w/ Linux & Apache) could someone suggest how to set up PostgreSQL, Geoserver, and ISS/Apache?

I've heard of GeoCommon as being an easy GIS solution, but I'd like to host the data locally for internal users. I know of a group called Open Geosuite - but the ongoing maintenance is something I'd ...
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Why does ST_Transform fail?

I got a postGIS error like this, ERROR: transform: couldn't project point (100.496 13.7118 0): latitude or longitude exceeded limits (-14) SELECT ...
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How to update constraints if the table name was changed?

I modified the name of a Table in postGIS. But the constraints contains old table name. How can I change the constraints? Please help me.
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How to offset point perpendicular to line direction in PostGIS

I have a postgis table of points, that are sitting on road centerlines (I've linear referenced them). And the second table with road centerlines themselves. The point table also has a field roadid and ...
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301 views

Why are Postgis sequences not automatically updating in QGIS?

I'm adding new features to a polygon datasets in QGIS. The data is held in PostGIS but when i have a look at the attribute table for the polygon the gid field is not automatically updating, the entry ...