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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1answer
2k 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 ...
2
votes
1answer
1k 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. ...
3
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3answers
3k views

How to import data with SRID 4269 to GEOGRAPHY type?

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 ...
0
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1answer
3k views

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 ...
4
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0answers
9k views

Create a stacked bar chart with matplotlib [closed]

I'm trying to create a stacked bar chart in python with matplotlib and I can draw my bar one up the other # -*- coding: utf-8 -*- import psycopg2 import matplotlib.pyplot as plt import numpy as np # ...
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1answer
1k views

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( ...
3
votes
1answer
416 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 ...
6
votes
1answer
3k views

Loading a raster using QGIS into a PostGIS2.0 enabled database

Following on from my attempt to install a postgresql 9.1 db with postgis 2.0 on windows 7, I am trying to figure out how to load a raster. I have successfully loaded a shapefile, and am trying to do ...
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2answers
453 views

PostGis, export Svg in pixels

I'm new to GIS. It is very intersting. I have installed Postgis, insert shapefile, get data in SVG without problem (ST_AsSVG). Now, I'd like to export the same svg but in pixel to add it on top of ...
8
votes
2answers
2k views

Force SRID in views in Postgis 2.0

I have a very tricky problem: I have a Postgis 2.0 database, used as datastore for Geoserver 2.1.3 I have a table with a geometry column (named shape), with SRID 4326 I have created a view like ...
2
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0answers
216 views

How could I make this PostGIS query run faster?

SELECT st_band(rast, 1), st_width(rast), st_height(rast), st_bandpixeltype(rast, 1), st_bandnodatavalue(rast, 1), st_scalex(rast), st_scaley(rast), st_upperleftx(rast), st_upperlefty(rast) FROM ...
6
votes
1answer
1k views

Are there limitations using a PostGIS out-db raster?

I have been trying to import a large raster into a PostGIS 2.0 database and hit a few stumbling blocks. Initially when I tried to import the raster using raster2pgsql, I would receive the following ...
2
votes
0answers
106 views

Are geotiffs with the embedded georeferencing information supported?

I am able to load raster data into my postrgreSQL data base however when I display in Quantum GIS the pixel height and width of the image is being translated into real world lat/lon coordinates, as a ...
2
votes
0answers
102 views

How to convert FROM Navit to PostGis or SHP?

I have a Navit BIN file which I want to use in PostGis or QGis, so I need to import it to PostGis or convert it to a shapefile. I have found a lot of information on how to convert data TO the Navit ...
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votes
1answer
441 views

How to create,store and retrieve the spatial data in postgresql [closed]

i am new to postgresql/postgis can anyone explain in steps about how to store the spatial data and retrieve the spatial data and visualise in map in a proper steps.. pls . its very urgent..
6
votes
1answer
3k views

How to find the nearest point by using PostGIS function?

table A: lat | long | the_geom | code | sign 13.8433095 | 100.6360357 | 0101000020E61.... | ABC | start_point 13.7544738 | 100.5459646 | 0101000020E6..... | ABC | end_point 13.4124215 | 100.6232332 ...
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vote
3answers
243 views

postgis under win 7 “on demand” not as a service

how do I install postgis2.0 under win 7 to run just on demand. I dont want to run it permanently as a service. Similary as the (nonspatial) mysql can be run on demand via the xampp-tools ...
8
votes
2answers
310 views

Moving existing hard drive with PostGIS data directory to a new computer

I have a new computer that is replacing an old machine that has PostGIS installed. The old computer has a 2nd hard drive where the PostGIS data directory is stored. I want to move this drive over to ...
1
vote
1answer
441 views

Adding table from Postgis

While trying to import a table containing raster data in QGIS , Raster column is not being imported ... I am getting following messages: Database connection was successful , but the accessible ...
0
votes
1answer
421 views

How to use ST_Length?

I want to calculate the lenght of the line inside the polygon. If I do this: SELECT ST_Length(ST_Intersection(ST_Transform('SRID=3035;LINESTRING(4000000 3000000, ...
3
votes
1answer
660 views

PostGIS 2.0 ST_Transform with Rasters cannot find custom SRID

I'm trying to calculate an average value in a buffer around a point. Given a raster in EPSG 4326 and a similar point, this is fine, except that the values will be skewed as they are not projected in ...
4
votes
1answer
366 views

gdalinfo gives no georeferencing information for a PostGIS raster

I have a PostGIS raster dataset which I am trying to access via GDAL. I've had various problems with making this work, so thought I'd try running the gdalinfo command to check that GDAL can actually ...
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0answers
102 views

Make a thumbnail of a raster in PostGIS

I'm fiddling around trying to create a thumbnail of a fairly large (originally 27MB) raster, chunked into 64x64 blocks. I've got the following and it works, quite well, but I'm wondering if there is a ...
6
votes
1answer
3k views

PostGIS - 1.5 to 2.0 easy update

I have a PostGIS 1.5 database and want to update to 2.0. I read that because this is major release I have to follow the 'Hard update' procedure. However the spatial data I have is only test data so I ...
1
vote
1answer
128 views

How to select data inside a tile?

I have an OpenStreetMap PostGIS database and would like to select specific data (for example all shops) of each tile (on a defined zoomlevel) on the planet. Is this possible to achieve and if yes, ...
3
votes
1answer
955 views

remove duplicate points based on a specified distance

i have a table of points with each point acquired on a specified date, by a specified source, and having a measured value. i want to consider points as duplicates if they have the same date and if ...
2
votes
1answer
732 views

PostGIS 2.0 and Postgres 9.1: ST_Transform => failed to load NAD27-83 correction file (Windowsx 64)

after making a clean install with the latest stable release of postgis (2.0) i can't perform any transformations: SELECT ST_Transform(ST_SetSRID('BOX3D(2644033.2454124987 ...
0
votes
1answer
458 views

Unable to Make PostGIS 2.0 - file not found

I am struggling to get the latest trunk of PostGIS to install on a fresh Mac running Lion. I did install PostGIS 1.5.3-2 for Postgres 9.1 from [KyngChaos Mac OSX Installers][1]. This setup worked ...