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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2answers
1k views

What's the fastest way to search for polygons that intersect with others?

I'm querying the database for searching polygons that intersect with others, but is very slow research, wanted to increase the speed. I thought of using sphinx, solr, elastic search googled but did ...
1
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2answers
221 views

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 ...
2
votes
1answer
53 views

How do I append PostGIS commands to the system path?

I'd like to be able to call psql instead of having to put in the full path everytime. I went into Environment Variables through My Computer and added the path to the semi-colon separated list, but ...
0
votes
1answer
367 views

What is the fastest way to identify the two nearest linestrings using PostGIS?

I want to be able to identify the closest roads to two points that are generated through geocoding (a start and end address). The points will likely be near a linestring. Two approaches that I have ...
6
votes
1answer
6k views

Postgis 2.0 - public.geometry_columns view does not contain correct info for views

We have recently updated our database to Postgis 2.0. In our system we used to create views for tables containing a geometry column. After creating the view we also manually updated the ...
12
votes
1answer
902 views

Are Zonal Statistics possible in PostGIS2?

Now with postgis2 which supports rasters by default is it possible to do a zonal statistics analysis? I've google it but I haven't found anything solid? Is there a tutorial outthere to get me ...
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
votes
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 (lat/...
0
votes
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
10k 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 # ...
-2
votes
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
426 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 ...
1
vote
2answers
471 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 this:...
2
votes
0answers
219 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 public....
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
110 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 ...
-5
votes
1answer
458 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 |...
1
vote
3answers
247 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 (http://www....
8
votes
2answers
320 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
447 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
432 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
672 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
372 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 ...
1
vote
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, how?...
3
votes
1answer
973 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
746 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 4580030.29781942,2645409....
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 ...