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

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160 views

How do I convert MultiLines to MultiPolygons using Postgis

In postgis I'm using the following query to buffer lines to polygons: UPDATE rivers SET poly = ST_Multi(ST_Buffer(lines, 0.01)) where id = 1; The column 'lines' is a MultiLine and the column ...
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0answers
107 views

Joining layers with respective elements with PostGIS Topology

Recently I have started using PostGIS topology extension, but I have some difficulties in understanding how the structure works: One of the key points is the use of "layer"s: as of what I understand, ...
2
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1answer
356 views

How to connect Postgis database with/in Remote Servers…?

I am preparing a 'Web based map' application using 'Geoserver-Openlayers-Postgis'... Now, I am trying to connect my Postgis database(located at 10.50.110.11 location) with the following command from ...
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0answers
31 views

error in loading raster tiles on postgreSQL [duplicate]

I am trying to import raster data from PostGIS to GeoServer. I follow the instructions given on this link. ...
5
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3answers
426 views

Snapping start- and end nodes of lines to other lines in PostGIS

There are plenty examples that show how to snap lines to points, but I haven't been able to find any (fast!) way of snapping the start- and end nodes of line strings to nodes of other lines. ...
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2answers
211 views

Emergency Services: How to optimize routing by measured travel time?

I would like to optimize the service areas / catchment areas for an emergency service. Therefore, I have several measurement points on the streetmap, where people have stopped the travel time from ...
5
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1answer
440 views

How to install PostGis on EC2 micro-instance

I tried to install PostGIS on my Amazon EC2 microinstance using sudo yum install postgis2 and got following error message: $ sudo yum install postgis2 Loaded plugins: ...
2
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1answer
167 views

Calculating points in the USDA's Cropland Data Layer coordinate system

I need to integrate against the USDA's cropland data layer. They've got a demo and some API docs. The important query I need to run is this, given an (x, y) of say (1551459.363, 1909201.537): ...
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1answer
90 views

Getting a “java.lang.OutOfMemoryError” error while importing raster files from PostGIS to Geoserver

I am trying to import raster data from PostGIS to GeoServer. I follow the instructions given on this link. ...
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0answers
178 views

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 ...
2
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1answer
126 views

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). ...
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1answer
1k views

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?
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1answer
142 views

ImageMosaic-JDBC Error

I'm trying to get postgis raster layers in geoserver-2.3.1, with postgresql-8.4, postgis-2.0 and gt-imagemosaic-jdbc-9.1.jar support. I'm going through the tutorial with a PNG raster that i have. In ...
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1answer
125 views

How can I check if a multipolygon can be represented as a simple polygon?

I have a large (30m+ records) spatial data set I have imported into a PostGIS database. I did not expect to find multipolygons in the data set, but it does have a few of them. I'd like to take a ...
3
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2answers
1k views

PostGIS: Convert meters to arbitrary spatial reference units?

I'm writing a query that needs to be able to work with data of any SRID. The basic problem is very simple - I get two pieces of information: A point (SRID = 900913) A distance (unit = meters) I ...
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1answer
307 views

How can I make a Postgres/PostGIS ST_Distance_sphere query more efficient?

Within Postgres/PostGIS I have written an SQL query to get the closest distance for each element within a point coordinate table from a polyline table. The query comes back and works correctly, but ...
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1answer
262 views

tinyows failing to connect to postgresql - Ident authentication failed for user “postgres”

I'm getting the above error on a new and local tinyows installation on Centos 6. Postgresql 9.2, PostGIS 2.0. I can connect to PostGreSQL locally and from my LAN using several other methods (psql, ...
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1answer
175 views

Cannot find my schemas in QGIS's “Add PostGIS layers”

When I connect to my PostGIS database using QGIS's Add PostGIS Layers, I see only public topology pg_catalog information_schema My other schemas that I have created are not shown here. Anyone else ...
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1answer
583 views

How to split line layer at polygons' boundary of a polygon layer?

I have a line layer and a polygon layer in PostgreSQL 9.2, PostGIS 2.0. How can I split every line each time it crosses a polygon's boundary?
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1answer
165 views

How to update SRID in PostGIS database

I am facing a problem when I am trying to execute few queries in PostGIS. It returns the following messages. ERROR: GetProj4StringSPI: Cannot find SRID (4326) in spatial_ref_sys ********** ...
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6answers
2k views

Unable to connect Postgis from QGIS 1.8.0

I have installed PostgreSQL and PostGIS on my laptop (Win 7 64 bit OS). I am running QGIS 1.8.0 on my machine . When I am trying to connect Postgis I am getting connection failed error then I tried ...
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1answer
375 views

PostGIS: Merge multiple table with same GID

I just imported some shapefiles with the PostGIS importer. Because several errors and issues I had to split my shapefile in multiple parts. Then I imported them one by one. I thought I can easily ...
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2answers
528 views

How to draw line in leaflet using postGIS road data

I have few points from server and I want to draw a line with this point on road. But the leaflet drawing point to point line as shown in picture in orange color. But I want to draw the line ...
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0answers
57 views

How a PHP script can perform point, line and polygon operation on Geoserver and PostGIS (+wkt) [duplicate]

I want to show my shape file and LULC map (vector and raster data) on internet explorer (locally). How should I configure PHP and Geoserver so that I can show data on localhost on an IE or browser? It ...
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1answer
299 views

How to show PostGIS distance in Meter

I have calculate distance from one point to a linestring. I have used the following query WITH data AS ( SELECT geom::geometry AS road_network from linestring) SELECT ...
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1answer
552 views

PostGIS ST_Contains question

Here's a quick summary about what I'm trying to do: Let's say I got two layers. One (A) with 10 polygons and one that is more granular with 100 polygons (B). Just to check if the behavior of PostGIS ...
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3answers
465 views

How to find lat/lon values for every pixel in a GeoTIFF file?

I want to a store GeoTIFF file pixel by pixel in the database. I need to store pixel values along with the lat/lon of that pixel on the GeoTIFF image. Is it possible to do that?
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1answer
2k views

Can POSTGIS 2.0 be install with POSTGRES 9.2 on Ubuntu 12.04 OS at the moment?

This question is more about environment set up. At the current moment, March 4th 2013, can POSTGIS2.0 be install with POSTGRES 9.2? I check their website out and to my understanding it is not ...
2
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1answer
407 views

How to import ECW into my postgis database with raster2pgsql (windows)

I'm working on windows 7 64 bits, postgis 2.01. I have to import ECW files into my postgis database. Unfortunatly, my postgis seems to has been compiled without gdal ecw support.When i do a ...
11
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1answer
203 views

Naming conventions PostGIS Database

We are starting to build up a database with PostGIS. The database is supposed to be for a team of about 5-8 researches who work frequently with geodata and statistics. Has anybody experience with ...
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0answers
254 views

How to import 3D geometries from DXF, VRML or X3D into PostGIS 2

we plan to develop a webbased 3D GIS using PostGIS 2 and GeoServer with a W3DS. The architecture works fine, but i have problems to import 3D geometries into PostGIS. The geometries come from AutoCAD ...
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1answer
232 views

How to properly use PostGIS with Maps

First time using PostGIS in an app. Target: - Get Heat Map of customers from address table using leaflet.js and heatmap.js Have DB called store_dev. Installed OSM Bright from Mapbox in it. Have a ...
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0answers
162 views

PostGIS 2.0 st_geomfromgml using LineString fails with invalid GML representation

I am attempting to insert a geometry into a table using the st_geomfromgml function. The GML is being sourced from a Geoserver WFS request. The function call looks like this ...
2
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1answer
36 views

Weird behaviour of ST_Project with PostGIS2

somehow I can't understand the results of ST_Project, but maybe this problem is just me being stupid (again): Note: I use geography-type here, but the results are the same for geometry. I use a ...
2
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1answer
446 views

generate height data from DTED maps

I have 16 DTED maps of (1 degree x 1 degree). I have to generate combined height matrix of maximum 4 (1 degree x 1 degree) DTED maps in my C++ application. Can someone suggest to me which open source ...
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1answer
406 views

Dynamically load and display shapefiles from PostGIS 2.0 into Mapguide using .NET

I have a C# mechanism for Loading shapefiles into PostreSQL/PostGIS now I would like to dynamically load it on Mapguide fusion template.In either C# or VB.NET code behind. Use case is: 1.use uploads ...
2
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1answer
90 views

problems setting up postgis and importing data

Using Postgres 9.2.3.1 on a new Mac. I installed Postgres from the dmg file that I downloaded from the Postgres site. I then installed PostGIS using stackbuilder. This all worked flawlessly so far ...
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0answers
158 views

Renaming Columns in Geotools FeatureType

I am attempting to build a simple java program that loads shapefiles into a Postgis 2.0 database. Everything is working out great except that I would like to be able to modify the FeatureType in the ...
2
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1answer
278 views

How to Find the Nearest Node from a Given Coordinate

I have already developed a table manually. It contains the coordinates and the distance of all the nodes, there is no geom field or any field related to postgis. But I want to find out the nearest ...
3
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2answers
867 views

PostGIS - incorrect result distance between two points

I am quite confused the way PostGIS is returning the result for this basic query. So I am trying to find the distance between two points 45.2714,71.2087 and 42.3739,66.39 and the distance should be ...
3
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1answer
274 views

Using PostGIS for a large trajectory dataset

I have a spatial trajectory dataset which basically contains about 10E6 (lat,lon,time)-tuples, grouped together by an identifier so they form trajectories. Currently, SQLite is used to store the raw ...
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156 views

Create Polygon Overlay Handling Holes

How can I create a polygon overlay that correctly handles holes? This answer provides a method of creating a polygon overlay that does not handle holes. Can it be modified to correctly handle holes? ...
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2answers
935 views

PostGIS SQL query to find a polygon that intersects with a line

I need to build a PostGIS query that would select every polygon inside an area the river is flowing through. I'd better describe with an example below: There is a river (blue line) flowing through ...
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0answers
64 views

how to group interconnected edges inside a table?

Given a table and a random set of edges with source and target columns, how can I find out which edges connect with each other and then group them together using PostgreSQL?
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0answers
48 views

given sets of vehicle passing on each edge, how to get most used vehicle to avoid transition?

I have two tables: one, the resulting table from converting osm.xml via osm2po so I can use pgRouting, and another one that contains information on what edges each public vehicle passes through ...
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1answer
437 views

Transit Routing using pgrouting as core routing engine?

i'm a student and i'm working on a project. the aim is given two sets of coordinates(origin & destination) route through the map to determine the optimum path using public transportation and of ...
2
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1answer
555 views

How to visuilze PostGIS data in GeoJSON format with PHP

I need to visualize PostGIS Geometry column as an overlay of a Leaflet tiled Map. I started a question here ,but didn't get any simple and satisfied answer. So I am starting this question. I got an ...
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0answers
680 views

PostGIS data visualization

I have dump my data in PostGIS from shapefile successfully. I made a postgres connection through PHP and that also returning the data of other field. But the main problem is GEOM field visualization. ...
5
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1answer
461 views

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 ...
7
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2answers
398 views

How to get distance between one point and all other points in a table?

I have a table in Postgres with lat and long columns. Can I use the ST_Distance_Sphere or ST_Distance_Spheroid methods to get the distance between one point and all other points in the table? Do I ...