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

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Postgis 2.1.1 compilation issue

Hi I tried to compile postgis-2.1.1 in RedHat 6.3 with: # ./configure --with-pgconfig=/usr/local/pgsql/bin/pg_config --with-gdalconfig=/usr/local/bin/gdal-config --with-geosconfig=/usr/local/bin/...
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158 views

Display postgis data with qgis 2.2

I have a problem with some shapefile, PolygonZ type, I have imported with "shp2pgsql-gui". This is the output (note 'coord_dimension' value): mode=c, dump=1, simple=0, geography=0, index=1, shape=1,...
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118 views

How can I optimize this point-linking query?

I have the following query, and am wondering how it could be optimised to run faster: WITH gps_nodes_1 AS ( SELECT "NODE_ID", "geog" FROM gps_nodes WHERE ST_Distance("geog",ST_GeogFromText('POINT( -1....
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3answers
441 views

Faster routing algorithm on pgrouting [duplicate]

I have downloaded data for india as a dbf file then converted it using osm2po to make it routable but the problem is when i make any routing query it takes a lot of time around 300 seconds and these ...
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517 views

ECW files to geoserver 2.4

I'm trying to add .ecw files (20 orthophotos) to geoserver 2.4. Geoserver is running on an ubuntu 12.4. Vserver. I'v already installed the GDAL plugin. Is this the right format for the import:...
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2answers
653 views

how to Find n nearest lines for the given points from a collection of lines?

I have two tables, points and lines. For each point in point table, I want to find out nearest 3 points in the nearest 3 cables. I almost developed a query, but it is best suitable for single point, ...
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1answer
547 views

ST_Intersects() in WHERE clause misses results

I have a table with a lot of geographical objects like countries, cities or points inside the cities. For instance # SELECT id, ST_AsText(location) FROM brace_brace WHERE id IN (3, 42); id | ...
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82 views

Forcing Hash Join Query Plans using PostGIS

I'm currently testing PostGIS 2.0 in a Greenplum Appliance (Postgres 8.2 based) and have hit an incompatibility between PostGIS and the MPP Greenplum environment. The basic query below can't be ...
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26 views

PostGIS two “circles” intersection [duplicate]

I am trying to see if two "circles" intersect. The data I have is two points and two radii (in meters). I am using srid 4326. My main issue (i think) is getting the radius in meters. SELECT (...
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1answer
480 views

Postgresql table won't display in QGIS 2.2

I just downloaded QGIS 2.2 to check it out and now one (just the one) of the tables from one of my PostgreSQL database won't display. It loads just fine in 2.0. The records are all there (there's ...
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51 views

Speed drastically reduced when including geometry, is there a way to improve?

-- EDIT: Issue is that the shape files being used are at too small of a precision and way too large, output was 488M total, looking for different source -- I'm having some speed issues with a complex ...
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1answer
658 views

Reprojecting in postGIS from 900913 to 4326. Wrong coordinates

I'm working with postGIS 2.1 I have a table called 'xacementos' created with the srid: 900913. I took the points coordinates from google maps and I want to convert them to SRID:4326 to show the points ...
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1answer
2k views

Transform projection from EPSG:4326 into EPSG:900913

. i've got this problem about projection. .i just wanted to know what am i missing. . i already displayed map base layer using openlayers through base_layer = new OpenLayers.Layer.WMS( "OpenLayers ...
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1answer
688 views

PostGIS: Faster way to ST_Clip() rasters with a polygon?

I want to clip an image with a polygon from postGIS rasters. What I do: - Import raster into postGIS(raster2pgsql, tile-size: 500x500, each tile contains 12 bands landsat 8) - Import a shapefile ...
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1answer
246 views

How to handle QGIS 2.2 Data Defined Label Position on PostGIS Layer Null Defaulting to 0?

I just upgraded to qgis 2.2 from 2.0. In 2.2 there was a minor change to data defined label positioning at least when used with postgis layers. In Version 2.2 the labeling engine appears to be ...
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3answers
123 views

How create geographic column in postgis table?

I merged several point shape files in postgis, but when I load the new merged shape in QGIS it is not possible to see points in the main window. To create the merged table I used this piece of code ...
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1answer
236 views

Replacing corporate GIS? [closed]

I'm looking at replacing our corporate GIS, this is the first time that I have had the responsibility of such a task despite my years of experience with the software as an end user. We will be ...
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1answer
313 views

How to access M-values in QGIS?

I am working with Linear Reference Systems and I know is very easy to get M coordinate (M-value) from a shapefile in ArcGIS. But, how to get the M-value in QGis? If you have doubts about my issue, ...
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1answer
679 views

PostGIS convert GeoJSON to geography

While there are functions to convert geography to GeoJSON: text ST_AsGeoJSON(geography geog, integer maxdecimaldigits=15, integer options=0); I do not see any way to go the opposite direction (...
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1answer
494 views

ArcMap reports that PostGIS polygon data is self-interescting

I have an ESRI File Geodatabase of data that I upload to PostGIS using FME. Seeing as I have to have the data in PostGIS for other purposes, it would be great to view the data in ArcMap straight from ...
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1answer
151 views

ST_AsLatLonText returns wrong data

I want to list all cities in lubelskie vovoidenship, which is relation 130919. I also want to get latLong data for each city. To perform this I do: SELECT name, ST_AsLatLonText(way), place ...
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278 views

How can I edit spatial data automatically on postgis and check for topology errors on said data whitout using shapefiles?

So, I have spatial data stored in postgis (points, lines and polygons) and would like to edit and update those in an Open Source software (quantum GIS, grass, etc.) to check for topologic errors, ...
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1answer
131 views

Problem with runing a loop in a query in PostGIS

I am new to PostGIS and I have a question which can't solve. I have a table of buildings each having a value for number of people living in it. I would like to calculate the total value (sum of number ...
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303 views

PostGIS: How to distinguish overlapping routes (i.e., LineStrings) based on their direction?

I have a set of routes which are represented by LineStrings in my PostGIS database. These routes represent journeys that people make. I want to come up with routes that (a) overlap, and (b) have the ...
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1answer
275 views

Problem with nested query in PhP and PostGIS

I have a simple problem regarding a nested query. I would like to select all buildings in a given circular buffer and create a kml file of those selected objects. The following query does the job very ...
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221 views

Problem with result of query in PostGIS

I run the following query and irrelevant of the point coordinates and radius I always recieve all the records of the table I'm querying. Can anyone point out what the problem could be with this query? ...
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3answers
5k views

Installing Postgis on Ubuntu 12.04: unmet dependencies libgdal1

After sudo apt-get install postgresql-9.1-postgis I got that massage: The following packages have unmet dependencies: postgresql-9.1-postgis : Depends: libgdal1 (>= 1.9.0) but it is not going to ...
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1answer
745 views

How can I transform polylines into points every n metres in PostGIS?

Question in pretty much the same as this, but I need to use PostGIS. I have a number of polylines, and want to trasform them into points every n metres along these lines. edit: Thanks a lot to ...
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0answers
154 views

How to set posgis default sequential value in a QGIS “editable” view?

Introduction In a QGIS project I have a VIEW, that I want to became editable (I'm trying to replicate the versioning system used DB Manager with some tweeks). Therefore I created a few rules to ...
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26 views

Postgis and osm2pgsql: find all cities that belong to selected state [duplicate]

I'm pretty new to postgis, so I don't quite understand it's mechanisms yet. My task is to build database with relations: +---------+ +------------+ +----------+ | country | | adm_unit ...
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1answer
318 views

Split and order lines by polygon intersection

I am using PostGIS and QGIS 2.2. I have a shapefile of rivers and a shapefile of state parks and other polygons. I would like to show the user a simplified version of a stream as a straight line, ...
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497 views

CartoDB st_makeline with geography datatype

Hi I am using an online cartodb account to try and create a shapefile based on flight routes between one airport and another. So far, I have uploaded my lat/long points for each connected airport, ...
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1answer
166 views

How can I combine two datasets with the same schema in to one table?

So I have two tables (in CartoDB/PostGIS) that are from two tiger shapefiles that have the exact same attributes, just in different counties. I want to combine them in to a single table, just ...
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1answer
55 views

Is rid=2 significant in PostGIS raster structure?

It seems that in most, if not all, examples with raster appear to include the WHERE rid=2 statement in the query. http://postgis.net/docs/RT_ST_Value.html Is there something about the rast structure ...
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1answer
757 views

ST_Transform not converting from utm to lat/lon

This line: ST_AsText(ST_Transform(the_geom, 4326)) Returns the "coordinates" as utm coordinates. Although, I thought ST_Transform was supposed to convert the coordinates from utm to lat/lon. I ...
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1answer
720 views

PostGIS Raster in MapServer

I'm having trouble getting a PostGIS raster to load and display in MapServer. I'm not sure, but suspect it's a version problem. My mapfile layer and the error message are shown below. LAYER ...
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1answer
230 views

Problem with using a circle as polygon for querying PostGIS

I'm trying to query PostGIS and find some object features that intersect with a circular buffer created by the user using OpenLayers, JavaScript and PHP. I use the following code for creating the ...
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124 views

Add memory layer to a preexisting PostGIS table

I'm trying to append a memory layer to a preexisting PostGIS table. The DB connection is already established (in this way: How to properly establish a PostgreSQL connection using QgsCredentials) and, ...
2
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1answer
525 views

Problem with reading data from PostGIS as KML file using PHP

I am using the following PHP code in order to read data from PostGIS and save it in KML format as a file. When I load the page a document with ".PHP" extension is returned (not .kml) which inside has ...
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2answers
145 views

Distance calculation PostGIS

I've got the following task to solve: I've got two tables; one contains buildings (houses) as points and the other contains train-stations (at_bhf_classified) as points. I need to find out the ...
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1answer
46 views

violates check constraint

I try to add a constraint based on geometry type to a "street" table that prevents anything except Linestring geometry or Null. alter table streets add constraint streets_geom_linestring_chk check(...
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24 views

pgrouting - possible to find route through points rather than links? [duplicate]

Probably a daft question, but... I've been looking at using pgrouting to analyse paths between start/end points, but this analysis seems only to find routes through links (edges). Is there any way ...
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0answers
238 views

How do I simplify the straight sections of (multi)Linestring in PostGres/PostGis leaving the curved sections untouched

I have (multi)linestrings containing upwards of 5000 points and I want to perform two simplifications possibly using Ramer Douglas Peucker or alternative methods in PostGis The (multi)linestrings ...
2
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2answers
701 views

Problem in running query on PostGIS using PHP

Would you kindly help me solving this problem. I'm trying to use the PHP code provided here in order to read geo-data from PostGIS. The code seems clear without any problem (also nobody has ...
3
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1answer
904 views

Most Efficient method of Storing Point Data in PostGres/PostGIS to later re-create a track

I am trying to determine the most efficient way to store point data in PostGIS to later re-create tracks Criteria: 1 second updates 100- 200 tracks active at any one time 1 hour max ...
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4answers
790 views

How to turn all lines into one direction?

How can I turn all features of my polyline (postgis and/or shapefile) into one direction - it doesn't matter what direction. I know how to switch the direction of lines but I have no idea how to ...
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1answer
155 views

Installing Cartaro using Acquia Dev Desktop and and link it with GeoServer and PostGIS

How do i configure GeoServer and PostGIS so that I dont get the following error when installing Cartaro using the Acquia Dev Desktop. I am just installing Cartaro locally for testing. Or how can ...
6
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1answer
3k views

Add PostGIS spatial functions to a custom schema other than “public” in PostgreSQL

I am new to PostgreSQL and PostGIS. Recently, I created a PostGIS 2.0.3 database on a PostgreSQL 9.1 database server using pgAdmin. The "PostGIS" extension was found installed in "Extensions". Al ...
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2answers
379 views

Unable to implement pgrouting(plugin) pgr_astar routing algorithm (shortest path) [duplicate]

I have been working on a project for indoor navigation. I made the floorplan of the building and road-map for routing purposes as shp files (using JOSM, making GeoJSON and then converting to shp file ...
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1answer
417 views

Problem connecting local POSTGIS in QGIS

I'm trying to connect to local POSTGIS database using QGIS. I'm using the POSTGIS Tutorial form Buondless (rif. http://workshops.boundlessgeo.com/postgis-intro/index.html). The context is the ...