PostGIS is an extension for the PostgreSQL object-relational database that adds support for geographic objects.
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76 views
Are there Open Source alternatives to ArcGIS Aggregate and Extract Value to Points?
I am looking for some kind of Open source GIS library which can perform spatial analytic functions same as ArcGIS.
My use case is : I am processing GeoTIFF file provided by USGS and performing ...
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0answers
14 views
Query Multipolygon from PostGIS database
I my OSM PostGIS DB there are multiple polygons in the planet_osm_polygon table with the same osm_id, my idea is that this must be the parts of a Multipolygon.
Now I want to query the Multipolygon ...
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0answers
20 views
Python OGR, psycopg, postgis - geometry is null when updating
I'm attempting a python script that takes data from a file and updates only the geometry and a key field in a post gis table. But no matter what I try the geometry always seems to be updated null.
...
2
votes
2answers
82 views
Why is sum of st_length() of segments 20% too big?
I'm running a query to return the total length of some bike paths, from OpenStreetMap. Compared to the known actual length of these paths, they're all a bit too big - something like 10-30%.
I know it ...
1
vote
1answer
38 views
Auto-increment id when adding a feature to a PostGIS layer in QGIS
when I enter edit mode of a PostGIS layer in QGIS 1.8 and add a feature, is it possible to auto-increment the ID? I always have to look what last used ID was and manually enter a new one. I can't ...
1
vote
1answer
50 views
Find nearest neighbours faster in PostGIS
I currently have a query that calculates the number of useful amenities within a certain radius of each town, using OSM data:
create table places as
select town.name, place, town.way, (
select ...
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0answers
22 views
How to write a point-in-polygon query for Postgis?
I'm trying to write a query in Postgis which will return all rows where a dynamically changing longitude/latitude point resides within the geometric polygon of that row (in the geom column). This is ...
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0answers
17 views
Easy way to set up a blank PostGIS database for OSM2pgsql?
When you install PostGIS you get one database 'gis' created for free. But soon I want another, then another. So far, the way I do this is by messing around with "CREATE DATABASE ... WITH TEMPLATE"...
...
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2answers
12 views
SQL query for raster point samping within postgis
I am trying to update my table with the values from a raster stored within the database.
Edit:
I've posted the answer bellow: http://gis.stackexchange.com/a/63655/6711
The query I'm trying to use is ...
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votes
1answer
45 views
Postgis max contains query
I have two tables:
CREATE TABLE periphereies
(
gid serial NOT NULL,
per character varying(60),
geom geometry(MultiPolygon),
CONSTRAINT periphereies_pkey PRIMARY KEY (gid)
)
WITH (
...
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0answers
27 views
How can I open gSSURGO Arcgis 9.2 personal geodatabase with QGIS?
I downloaded the gSSURGO from the usda geospatial gateway yesterday and was disappointed to find that (at least in New York) it was only available as an arcgis 9.2 personal geodatabase. I did a bit ...
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vote
2answers
34 views
Problem with PostGIS in Opengeo Suite in Ubuntu 13?
Everything is working fine after installing the Opengeo Suite in Ubuntu except PostGIS issues. In the dashboard the PostGIS manage is disabled(grey) but PostgreSQL is working via pgadmin3. And also ...
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votes
1answer
14 views
Mapserver mapfile with multiple layers that pull from postgis only gives broken image
I'm trying to use this mapfile that I made:
MAP
IMAGETYPE PNG
EXTENT -90.000124 41.000032 -88.000044 42.000035
SIZE 1600 800
IMAGECOLOR 255 0 1
OUTPUTFORMAT
NAME png
DRIVER AGG/PNG
...
1
vote
2answers
37 views
Insert into X coordinate separately?
I have a postgis table with a point geometry for lat/long but i want to run a query that inserts a new row with lat, long values separately instead of concatenating them into a geometry.
so is there ...
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0answers
22 views
Query OSM ids by name in PostGIS
I installed PostGIS on a server and now I want to query the OSM ids referring to a name, in order to get a list of all geometries according to this name.
Is there an efficient way to query this ids ...
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0answers
18 views
Fatal error: Call to undefined function pg_connect() in /var/www
I have seen this error online, I have followed the online instructions. However when i do this and restart wamp it wont load up, it stays amber, as soon as i recomment in the lines and restart wamp ...
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1answer
23 views
How to load layers from postgis to dotspatial or sharemap viewer
I want to develop a PostGIS viewer for PostgreSQL (with SQL query editor) to visualize PostGIS layers.
Which spatial library (.net C# supported) do I have to use?
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votes
1answer
24 views
PHP PostGIS to geoJSON missing required parametar error
I'm using this PHP PostGIS to geoJSON script: https://gist.github.com/bmcbride/1913855
But I keep getting this error: 'missing required parameter: geotable'
This is my code:
# Retrive URL ...
1
vote
4answers
57 views
Web service to see postgis polygons
Is there any website or web service where I throw a polygon postgis and he show me on the map this polygon.
Example:
I put this
POLYGON((0 0, 1 0, 1 1, 0 1, 0 0))
and the service show me the ...
1
vote
0answers
19 views
windows function with points in a mixed (multipoint/point) table
I have a table comprising multipoints (tracks) and points (stops between tracks). there can be several consecutive multipoints.
now, i want to merge any points lying very closely to each other ...
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votes
1answer
25 views
I have line strings in points and need to conver them to lon/lat degrees
I need to convert line strings back to latitude & longitude coordinates.
Here are is an example, please keep in mind that they do NOT reference the same point. I have included the values to ...
2
votes
1answer
38 views
Is it possible to update only latitude or longitude in postgis ?
I have a postgis database that contains Points created based on a couple (longitude, latitude), and I need to update only one of those two for a given point.
I found that it's possible to do so but ...
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votes
1answer
34 views
java.lang.NullPointerException with GeoServer and Postgis
I am continuing work that another person began based on Geoserver and postgis. On the database level there are many tables and the layers are views based on these tables. That is working great!
Now I ...
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1answer
30 views
geoserver problem to join sql-server table to a layer
i have a layer published on geoserver based on a connection to a postgres/postgis Table and i need to add another table existing on sql server to do a data jointure table to table in order to add ...
1
vote
1answer
52 views
Loading PGadmin III GUI Linux
Having tested out the functionality of OpenGeo Suite Community, I have installed the Linux version on my Centos 5 Server. However unlike in windows the dashboard is greyed out for Post GIS. I believe ...
2
votes
1answer
53 views
Help building SQL query to get a list of streets of a city
From two layers in PostGIS (osm_places and osm_roads), I would need to have the roads belonging to a certain city.
It would be fair enough to get the street names of all streets in a radius of X ...
0
votes
1answer
29 views
Conversion from 3 dimension geometry to 2 dimension
I have a Point table in which the geometry column contains both 3 dimension and 2 dimension values.I want to convert this 3 dimensional geometry to 2 dimension.Is there any function in PostGIS? Please ...
1
vote
1answer
45 views
Algorithm to find the polygon ID where a point belongs to
I am wondering what is the simplest way to perform a look up of polygon Id based on the point location.
Input: a point with coordinates, a table of polygons
Output: the polygon Id where a point is ...
1
vote
0answers
23 views
Geoserver - empty native SRS field
I'm converting layers from shape files to postgis with the below command:
shp2pgsql -s 22175 -c -W "latin1" path/file.dbf' table_name db_name | psql -d db_name
Next, I add this layer to the ...
1
vote
1answer
49 views
In PostGIS, how do I merge a multilinestring into a single linestring, keeping the pieces in proper order?
I have a multilinestring made up of several pieces, some of which are facing the wrong direction.
(Accessible here: http://pastebin.com/89Zcixv5 )
I think what I'm looking for is some utilization of ...
2
votes
1answer
57 views
Geoserver 2.3.1 not finding all columns from PostGIS connection
so I am not sure if I have missed something or this a particular problem with this version of Geoserver. I want to style a point layer with a SLD, based on values in a particular column. The column is ...
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votes
0answers
36 views
several fields and GEOMETRY GetFeatueInfo from Geoserver
Good day!.
I have a table in PostGIS 2.0 with several fields of type GEOMETRY. In the geometry_columns they are published in Geoserver 2.2 as layers. This is done as here - geoserver docs, but ...
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votes
1answer
41 views
How to join two table based on one unique column in PostGIS
I wonder if there any simple query that perform just like Join features of ArcGIS Desktop.
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votes
1answer
57 views
It seems there is a bug in St_Clip function of PostGIS
The code I am using for clip feature is :
raster ST_Clip(raster rast, geometry geom, double precision[] nodataval=NULL, boolean crop=true);
I tried clip a shape depends on the polygon from the ...
1
vote
1answer
58 views
Distance between DB field and Point using PostGIS
I'm using Postgresql 9.0 with PostGIS 2.0 extension.
I've got the table and geographic field location:
=# SELECT * FROM geography_columns;
f_table_catalog | f_table_schema | f_table_name | ...
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votes
1answer
26 views
st_linemerge does not work
I have two LINESTRING's which intersect by checking with st_intersects. Then i try to collect/union both linestrings into one Multistring, then try to merge with st_linemerge, but it fails with:
...
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votes
1answer
33 views
ST_Touches for more than just one geometry
I'd like to select some neighbor polygons with ST_Touches. Therefore I found the following statement:
SELECT b.name
FROM layera as a
JOIN layera as b
ON ST_Touches((SELECT a.geom FROM layera as a ...
3
votes
2answers
56 views
Performance of Postgres VIEW published in GeoServer
Does anyone know what will be the performance difference between publishing a spatial table directly vs. creating a view of the same table and publishing it in GeoServer?
Does the spatial index on a ...
0
votes
2answers
71 views
Can't read returned geojson
I've got a function that takes an Openlayers mouse click and puts the click location into a SQL statement which then gets passed to a JSP script which runs the SQL statement on the PostGIS database ...
1
vote
0answers
49 views
Rendering geoJson polygons in google maps android apiv2
I'm in the process of publishing spatial data stored in a postgis database to a google maps based android app and am trying to put together a plan for rendering my data in the most efficient manner ...
0
votes
1answer
46 views
SELECT assign_vertex_id('ways', 0.00001, 'the_geom', 'gid'); not work
I'm using using OSgeo 6.5 dvd and studing pgrouting workshop (link) for get shortest path. I created network topology call "pgrouting - workshop". There are three commands to execute in section 5.2 ...
6
votes
1answer
87 views
Database Diagrammer for PostGIS [duplicate]
Is there a application, or QGIS plugin to generate database diagrams (specifically for PostGIS) similar to the ESRI Diagrammer?
Thanks...
1
vote
0answers
22 views
How can I combine these two commands? (Get a clipped raster ASC-II file from PostGIS)?
My objective is to clip a polygon from PostGIS raster table, and then save this raster (draw polygon shape) as an ASC-II in a folder. What I did now are 2 steps.
1st Step: Insert the clipped raster ...
1
vote
1answer
54 views
Create a network topology for pgrouting with grade separation
I have built a network using Ordnance Survey's ITN data and I can solve routes across the network. What I need is to build in grade separation topology for overpasses and underpasses on the network so ...
1
vote
1answer
58 views
Importing MaxSea 3D Database to PostGIS
I am currently working on a project, where I combine several MaxSea 3D databases, which contain depth measurements made by the echosounder onboard on a ship. The idea is to combine these databases to ...
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votes
0answers
35 views
Compiling PostGIS fails when it can't find GDALAllRegister
I'm trying to compile the latest PostGIS 2.1.0 beta and the configure process fails at:
checking GDAL version... 1.10.0
checking for OGR enabled... yes
checking gdal.h usability... yes
checking ...
3
votes
0answers
28 views
What is the correct syntax for using gdal_rasterize with a PostGIS datasource
I have a multipolygon layer in PostGIS and I would like to use gdal_rasterize to generate a raster. I cannot find the correct syntax to specify PostGIS as the data source.
$ gdal_rasterize -a ...
1
vote
1answer
62 views
Solution for slow display of postgis-tables ? (qgis 1.8 + postgis 2.x)
I have the problem that my postgres-tables are displayed very slow when I scroll them in QGIS. I have no problem with other tested GIS (e.g. UDig, GVSig, ArcGIS). The number of objects isn't large ...
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votes
0answers
21 views
Solving flagrant shared object errors when compiling postgis 2.1SVN from source on Ubuntu 12.04
I have spent the past few days of my life trying to figure out how to get postgis to function properly with a non-standard directory installation of postgres 9.3, but have been unable to resolve the ...
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vote
1answer
85 views
How to populate the geometry column in a PostGIS table?
After loading a polygon shapefile into PostGIS, the geometry column (geom) is blank for several features. In one case, only a single feature has the geometry calculated and all others are blank.
I'm ...
