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

learn more… | top users | synonyms

3
votes
2answers
421 views

small difference in projection between tilemill and postgis

I would like to create a world map with interaction on continents created directly from a postgis database. For the moment, I have a POSTgis database with the data. I created a background with ...
3
votes
1answer
606 views

Making calls the PostGIS functions with Java

We have Java stored procedure in Oracle that make calls to functions offered by Oracle Spatial to perform spatial analysis and return results. I am looking to the same in PostGIS, is this possible?
3
votes
1answer
4k views

How to get the coordinate system from a PostGIS database?

My question is probably amazinlgy stupid, but I can't find the answer myself. I would like to extract from a database the latitude and longitude of points. For now, I'm getting x(the_geom) and ...
3
votes
1answer
1k views

Postgis: Is there a way to do an intersection query based on lines while taking into account the dateline?

This is an exact copy of a question I asked on Stackoverflow a few weeks back and still haven't found a good answer for it. The original question is from here: original question. I've been searching ...
2
votes
1answer
29 views

Preprocess OSM streets to see if query points fall “on” them

I am interested in the following query: Given a set of query points ($\leq 10$), how many of them have distance at most $s$ meters to the closest point on the closest street. What's the most ...
2
votes
1answer
68 views

Running Gevel on PostGIS 2.0

I have found Gevel, a tool enabling the visualization of the content of the GiST indices in Postgres. In particular, I am interested to use it to visualize the RTree spatial index in PostGIS. Does it ...
2
votes
1answer
152 views

Convert a raster to GeoJSON polygons in PostGIS

I'm trying to convert a raster to a polygon and export it from PostGIS as GeoJSON. Specifically I want each pixel to be a polygon with associated the raster value. PostGIS seems to have a few ...
2
votes
1answer
60 views

Generating Shapefiles from PostGIS as a Plugin

I used to generate shapefile from PostgreSQL database that is installed with PostGIS tables as templates (geometry_columns and spatial_ref_sys) Shapefiles generated just fine using the following ...
2
votes
1answer
178 views

osm2pgsql Ways importing very slowly in .pbf, much slower than .osm

I'm currently importing the planet-latest.osm.pbf file I downloaded from ftp://ftp.spline.de/pub/openstreetmap/pbf/planet-latest.osm.pbf some time last week. I'm importing it using the following ...
2
votes
2answers
123 views

Looking for boolean intersection of small table with huge table

How can I quickly check to see if a polygon(or whatever) intersects anything in a massive table? I'm trying to find polygons that don't intersect with the North American street network at any point. ...
2
votes
0answers
163 views

Is there any VRP solver in Pgrouting 2.0?

after looking at older posts and googling for a while i guess there is not vrp solver (multiple trucks). there was DARP in pgr1.x but i can't see it in 2.x. i found a lot of information on ...
2
votes
1answer
131 views

Coloring multilinestringzm M values in QGIS

I have output from a geophysical technique that produces X,Y,Z and scalar value for millions of points, which have been stitched together appropriately (by networkx if it matters) into ...
2
votes
0answers
124 views

Geoserver : create a rasterized polygon / dynamic fill for polygons with features from database

I decided to post here because I couldn't find any answer to my problems on the internet. So I am using geoserver 2.7-SNAPSHOT, everything is working fine but I need to implement a new function or ...
2
votes
1answer
143 views

How do I get the vector and raster metadata from a PostGIS database?

im using php/postgres/postgis in a webapp, im wondering if its possible to get metadata from the db about all shp/geotiff table like (name, projection, type(ship/tiff), date, desc, owner etc ...) i ...
2
votes
1answer
168 views

PostGIS GML round trip confusion

I've investigated the issue of coordinate order in GML and each time I think I've got it but I find my self confused once again. I think some of my confusion may be to do with PostGIS. Doing a ...
2
votes
1answer
113 views

QGIS select reversed geometries

I have a road network and a geometry for each road direction. One Geometry from A->B and another Geometry from B->A. This geometries are covering each other. Is there a tool available in QGIS to ...
2
votes
1answer
99 views

Redefining the border of a polygon in Postgis

I have a PostGIS algorithm that writes a table with "pixelated" polygons, that I will call "clusters". My idea is to smooth the edges of these clusters using concave hulls (ST_ConcaveHull). To do ...
2
votes
1answer
178 views

Databases supporting intersection of multipolygons and a set of points

Currently we use PostGIS to store thousands of MULTIPOLYGONs and we can then use ST_Intersects to return any that rows contain any point in an input collection of points. Are there any other open ...
2
votes
2answers
175 views

Did I set up Tiger Geocoder incorrectly?

I set up Tiger Geocoder in PostGIS on my local box (PostGIS 2.1.3, PostgreSQL 9.3.5, Tiger 2013 data). The problem I'm running into is that on almost every street most of the points are clustered, ...
2
votes
1answer
214 views

PostGIS - How do I create a line that directly connects two earth points without travelling over a geodesic?

In PostGIS 2.1.1, I've noticed that if I create two distant earth points with equal altitude and then create a line connecting them, as I gather interpolated Z coordinate data along the line my Z ...
2
votes
1answer
165 views

SDO_Inside equivalent in PostGIS for 3D objects

I am looking for a solution for querying a point whether it is located inside a 3D object or not. If the point is located on the surface of 3D, I could use ST_3DIntersects or ST_3DIntersection. But, ...
2
votes
1answer
763 views

Spatial joining syntax

A standard PostGIS point-in-polygon query might look like this. (example tutorial) SELECT p.*,b.polyname FROM points p, shapes s WHERE ST_Within(p.the_geom,s.the_geom) Imagine this was not a ...
2
votes
1answer
595 views

How to calculate the shortest distance for multiple source and targets using PgRouting?

I have a table with points and a road network which includes driveways (where you enter the highway). I want to find the point which is closest to a driveway. So I was thinking I can calculate the ...
2
votes
1answer
3k views

PostGIS Column has Z dimension but geometry does not

I am able to create a geomtry column for 3d multiline using this: CREATE TABLE trajectories ( gid serial NOT NULL, vehid character varying(10), state integer, geom ...
2
votes
1answer
531 views

How to generate pgrouting source and target with OSM?

Is there anyone here can explain me more details for pgrouting's source and target? I'm wondering how to generate with the given lonlat in OSM PostGIS entities. In pgrouting's website, they are ...
2
votes
1answer
694 views

Empty geometries in GEOMETRYCOLLECTION

I just noticed some strange behavior in PostGIS, with respect to WKT parsing. A GeometryCollection containing 1 or more empty geometries postgis_test=# SELECT ...
2
votes
1answer
269 views

Why is the QGIS 2.2 database tab missing?

I have recently installed QGIS-2.2.0 but the Database tab in the top-menu bar is missing. It looks the main reason is missing libgdal1h library. But when I am installing it, it's removing ...
2
votes
1answer
1k views

PostgreSQL : finding all lines intersecting with a polygon

I am totally new in the world of GIS but as a student surveyor I am working on a project using postgreSQL and PostGIS. I have one database with all the roads of my country (lines), and one database ...
2
votes
1answer
273 views

When would a PostGIS geometry compare using ~= return true when ST_Equals returns false?

I have a couple of featureclasses in a 10.2 geodatabase/PostgreSQL 9.2.2 database and I've been struggling with the FeatureCompare tool--it is telling me geometries are different on some features ...
2
votes
4answers
250 views

Linking up GPS points taken from rail network

Bit of a newbie here, trying to work out whether any PostGIS functions can help with my task. Apologies in advance if my use of GIS terminology is not up to scratch yet. I have a large database of ...
2
votes
1answer
114 views

PostGIS: How to understand ST_RasterToWorldCoord() right? (PostGIS 2.0)

After putting raster in to postGIS by this Thank @Sorin for helping me out! Now, I want to output raster tile, then view it on QGIS. But the problem is the output of ST_RasterToWorldCoord(raster ...
2
votes
1answer
173 views

How to change table name of command raster2pgsql

I am completely newbie with GIS and PostGIS as well I'm trying to load raster into postgreSQL with raster2pgsql. It runs well. However, the table name of the raster is generated automatically. For ...
2
votes
1answer
2k views

Having trouble connecting QGIS with postgres database with postgis extension [closed]

I am working on Ubuntu Precise with postgresql version 9.3 and postgis 2.0. After initially starting my postgres database and eventually getting permission errors that would prevent postgres from ...
2
votes
2answers
475 views

ST_ShortestLine gives different results for 4326 and 900913 projections. Which is correct?

I'm trying to get my head around how ST_ShortestLine (and ST_Distance and ST_LineLocatePoint) work with different projections. The result for the shortest line differs depending on which projection I ...
2
votes
1answer
1k views

GeoTools and PostGIS with ESPG:3857

I'm trying to use both PostGIS and GeoTools with the same ESPG:3857 projection, however, it looks like the projections in PostGIS and GeoTools differ. This is what I have in PostGIS: PROJCS["WGS 84 ...
2
votes
3answers
1k views

Why can't I open postgis layers in QGIS?

I've set up a table in PostGIS using OSM data (converted using osm2pgsql). I know this database is good, because I'm able to import it and work with it in TileMill, but whenever I try to interact with ...
2
votes
2answers
686 views

Can Geoserver return the raster value of a lat/lon point

I have a GeoTIFF published by Geoserver 2.2 and being used by Leaflet via WMS. How can I get Geoserver to return the raster value at a lat/long point? I'm guessing it has to do with using WCS, but ...
2
votes
2answers
3k views

QGIS: using postgis can I define a layer using sql?

I have a vector layer (call it master) that is stored in postgis and consists of a number of line segments. I also have a collection of sub layers that consist of subsets of the master layer. I can ...
2
votes
1answer
598 views

Problem connecting to localhost PostGIS

When I try to connect to a small localhost PostGIS database using QGIS, I get the error message: FATAL: no pg_hba.conf for host "fe80::4528:3236:418a9e7b%10" user "postgres", database "nyc", SSL off ...
2
votes
2answers
2k views

KML from EPSG:4326 to EPSG:900913

im trying to create KML files manually (XML format) by extracting data from a postGIS database with "geography" values in a column. But i belive i need to transform the projection of each row in the ...
2
votes
0answers
812 views

why preview image is blank for ImageMosaicJDBC (postgis raster) layer?

I follow http://docs.geotools.org/latest/userguide/library/coverage/pgraster.html to publish a ImageMosaicJDBC layer in geoserver. the layer seems published ok and saved, but the preview of this layer ...
2
votes
1answer
1k views

How can I fix QGIS PostGIS Manager error 'shp2pgsql' is not recognized?

I have QGIS 1.8.0 installed via OSGeo Installer and work on win 7. All I need is to upload the shapefile to the database via this plugin. Unfortunately I am receiving an error: Something's wrong: ...
2
votes
0answers
335 views

From pgRouting shortest_path back to osm node id

I'm successfully performing path finding queries like shortest_path on data imported with osm2pgrouting. The tables I have inside my pgrouting DB are the following: List of relations ...
2
votes
4answers
2k views

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
2
votes
2answers
4k views

PostGIS convert geography(Point,4326) to GPS

I got a database with a column of type geography(Point,4326), the data contained looks like 0101000020E610000092E057F66EF73140930035B56CBD4840. How can I convert it to GPS coordinates?
2
votes
3answers
1k views

adding non spatial attributes using geoserver

I am using Openlayers + geoext to perform transaction operations in postgis database using geoserver . i can insert spatial data into postgis but cannot insert other data like road name, road type in ...
2
votes
1answer
633 views

Accessing PostGIS raster data using Query Layer in ArcGIS Desktop?

I tried to load raster file (jpg) into post gis using the syntax provided here "C:\Program Files (x86)\PostgreSQL\9.1\bin>raster2pgsql -I -C -e -Y -F -s 102003 -t 300x300 ras_test.tif ras_test1 | psql ...
2
votes
2answers
2k views

Select Duplicate Points PostGIS

I have a table made of merged point datasets in PostGIS. I want to select all of the features where two or more points have identical geom values. At present I just want to select so I can review ...
2
votes
1answer
671 views

The minimum bounding circle of geometry that crosses the 180th meridian

Background: I've been given a task where I have to calculate the minimum bounding circle of Alaska (for the purpose of running a Roeck test). I'm using the Census' state level geometries available ...
2
votes
1answer
4k views

Basic MapServer query of PostgreSQL/PostGIS database

I've just installed MapServer on a linux server and I am trying to understand how to display a basic map using a PostGIS database. I have displayed a shapefile in the browser, so I know that the ...