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

learn more… | top users | synonyms

1
vote
1answer
60 views

QGIS/PostGIS layer styles

I've made a plugin asking for login credentials to a DB. Once logged in, the plugin is loading some layers from the DB. In the DB there are both admin and "normal" users. I've saved two styles to the ...
1
vote
0answers
35 views

Geoserver WFS Fails to Load in OpenLayers

I'm working with Postgis->Geoserver->openlayers on localhost. I followed a Geoserver tutorial to import some nyc sample data into my postgres/postgis database and link it to Geoserver. The layer ...
1
vote
0answers
21 views

ST_SplitRight() in PostGIS?

I am looking to split a shapefile via a line. I am interested only in the feature that lies to the right of the line; exactly what ST_SplitRight does here. Do any of you know of a way to do this in ...
0
votes
1answer
25 views

How to solve an instalation problem requiring “liblwgeom” to work with “shp2pgsql”

I am trying to import shape file to postgis. I have problem configuring shp2pgsql. I am getting this error : dyld: Library not loaded: @loader_path/../lib/liblwgeom-2.1.1.dylib Referenced from: ...
0
votes
0answers
25 views

PostGIS: calculate width/length of rectangular surface

I have rectangular shaped surfaces (multipolylines) and I need to calculate the width and/or length.. they have a rectangular shape but they're not real rectangles. Is there a way to do this ?
0
votes
1answer
26 views

Postgis add Geography to function()?

i was wondering im getting different results when using geography() on different positions within a query. So, whats the most accurate way of forcing geography() over a functions with geometry ...
0
votes
0answers
7 views

PostgreSQL : send all rows of a table to a function [migrated]

I have a table with one column (double precision numbers). I also have made a function (with double precision numbers as input and output), and I want to send every value of my table to the function, ...
2
votes
1answer
80 views

System requirement specification for Big Data Postgesql, PostGIS, and GeoServer based service

I want to start a GIS portal for around 3000-5000 visitors per day. MY database will be of an approximate size of 10 Terrabytes. The maps and layers are moderately complex, satellite-map overlay is ...
0
votes
0answers
28 views

PyQGIS loading layer style with PostGIS

I'm loading layer styles from .qml files in a Python plugin. I'm about to switch to loading them from a non-local postgreSQL db. I've been looking at the (from QgsVectorLayer (v2.2)) ...
0
votes
1answer
35 views

Increase Map Availability in Geoserver [duplicate]

I have an application which access same map from two geoserver using loadbalancing concept the map is accessed using WMS service. where the two geoserver connected to a single same POSTGIS database. ...
2
votes
2answers
55 views

What is wrong with how I am using ST_Within?

I am learning postgis 2.1. I created a postgis table from a shapefile and imported it into the DB. It made a table like this: db=# \d districts ... geog | ...
0
votes
2answers
56 views

can't geocode with PostGIS 2.1.1

I don't know where's the mistake... I am using the process from the PostGIS documentation (http://postgis.net/docs/manual-2.1/postgis_installation.html#loading_extras_tiger_geocoder) . I created a ...
2
votes
2answers
72 views

ESRI projection to SRID?

I am looking at MapX and MapY coordinates. The docs say they are "truncated State Plane coordinates: NAD 1983 State Plane Louisiana South FIPS 1702 (US Feet)." I am trying to reproject into a common ...
0
votes
0answers
20 views

Double version of PostGIS installed on my server

For some reason I messed up an installation of Postgis on my PostgreSQL 9.2.8 server. I had version 2.0.3 installed and when I tried to upgrade to 2.1 it did so. The problem comes when I dump the ...
0
votes
0answers
25 views

PostGIS 2.1 error install with shared object (rtpostgis-2.1.so") Linux Mint

I've Installed Linux Mint 16 mate and install PostGIS with PostGreSQL (I've tried many ways in the Internet from original source to some suggestion) but all is too error: " ERROR: could not load ...
2
votes
0answers
38 views

PostGIS does not export shortest path to Shapefile

I am trying to draw a bunch of lines overlaying the globe map in a WGS84 projection. To this effect I have created a PostGIS DB with a table that has one column containing linestring data. My problem ...
0
votes
2answers
118 views

How to install PostGIS and OpenLayers plugins?

I am new to QGIS and have installed the QGIS v 2.2.0. For adding google map as a base layer I need to install OpenLayers plugin. I also need to add the PostGIS plugin for DB management purpose. Can ...
2
votes
1answer
32 views

POSTGIS: function st_collect(geography) does not exist

I am trying to use some Geography functions, but I am getting an error that (all) functions are not existing. I have checked other Stackexchange posts (e.g. this one), but the solutions did not work ...
3
votes
2answers
70 views

How <-> operator work?

I'm doing a search to find links close to a point. The problem is if i limit to 20 result i found the closer link at 6mts but if i limit to 10 result that link doesnt appear and the closest link is ...
2
votes
1answer
37 views

Can you do ST_Transform on geographies?

I am brand new to postgis. I just learned that geometries model simple cartesian objects and that geographies model shapes on the surface of the earth. I have a bunch of data in columns X and Y of a ...
4
votes
2answers
134 views

How can I GROUP BY linear spatial clusters with PostGIS?

I have a series of points in a horizontal line, arranged into discrete spatial clusters by the underlying data pattern. Here's an example of what they look like: How can I use PostGIS to group them ...
1
vote
1answer
22 views

Does the psql prompt have a working directory in the file system?

I am learning postgis. This tutorial says "Navigate to where you downloaded the shapefile." Does that mean navigate to this location in the #psql prompt or navigate to this location with the $propmt? ...
0
votes
0answers
61 views

How to add a Geoserver WFS layer with data imported from PostGIS to OpenLayers?

I know that there are very similar answers to my question but I just can't find how to solve this problem, so I am wondering if my case is different or if I am doing something wrong here. I am trying ...
2
votes
0answers
29 views

PostgreSQL : Question about dropping tables inside funtions

I am writing a PostgreSQL code where I have a function wich is used multiple times in a single query with different input values. Inside the function I create some tables and use them. What is the ...
0
votes
2answers
50 views

ST_NumInteriorRings not returns zero, is a bug?

I am using PostGIS v2.0.3, the guide say that ST_NumInteriorRings "will work with both POLYGON and MULTIPOLYGON types but only looks at the first polygon. Return NULL if there is no polygon in the ...
2
votes
1answer
36 views

PostGIS Type Modifier Error

I'm trying to work an example from the "PostGIS Cookbook" and I'm getting an error I don't understand. I'm running the example using Postgres.app on a MacBook. Postgres.app is running PostgreSQL ...
0
votes
0answers
30 views

PostGIS : check if 2 lines are at contrary sides of third line

I am looking for a workflow to select a line on the condition that it is located on the contrary side of a middle line. So there are 3 lines (2 are given, 1 I want to select). I don't need you guys ...
2
votes
1answer
33 views

PostGIS create read only user for QGIS

I am having issues reading spatial tables in QGIS with a select-only "reader" user. I can create the reader user to access regular postgres tables like this: GRANT USAGE ON SCHEMA test TO reader; ...
4
votes
2answers
108 views

How to speed up a query for nearest linestring to point data

I have processed a Strahler stream order layer with a lot of river linestrings (type: Multilinestring) and their corresponding strahler number (see information here). Besides I have a point layer. I ...
1
vote
0answers
32 views

Do ArcGIS clients that direct-connect to postgresql/postgis databases override configuration settings?

I went in to modify some settings on a Postgresql database via the PGAdmin config editor and some of the settings don't have their default values and they are higher because they've been overridden ...
1
vote
1answer
29 views

Osm2pgsql crashed on import. Can I continue with what has been imported so far?

I recently imported the osm planet file using osm2pgsql. The process crashed (hung my whole box) when creating the geometry indices and other indices on the tables. Scouring through the source code, ...
2
votes
1answer
55 views

PostGIS : I want to use ST_OffsetCurve with MultiLineStrings

I need to use the function ST_OffsetCurve for a multilinestring, but PostgreSQL gives me the error that the function is only for Linestrings. Is there a way arround? I want to use the function ...
3
votes
1answer
63 views

polygon from exterior points

How to convert points data to polygon, so as to form polygon from exterior point as shown above
4
votes
2answers
78 views

pgAdmin vs psql

I have downloaded postgreSQl 9.3 and Postgis 2.1 recently as an educational adventure and have been working with both through the pgAdminIII interface. I haven't used psql yet when working with my ...
1
vote
1answer
49 views

Update postgres/postgis point data attribute from another enclosed polygon shapefile in QGIS

I have a placename point table in postgis with 'district' column. a districts polygon shapefile with district name in 'Name' column. See the image below. I would like to update the 'district' ...
0
votes
1answer
42 views

Polygon feature in PostGIS

I have uploaded a feature to the PostGIS db and visualize it by mapguide. Now I would like to know how can I update (add) features from database directly. Can I add a new row from the web form ...
1
vote
1answer
37 views

Create geometry from decimal lat/lon instead of degrees

Creating a geometry in postgis is fairly simple: ST_SetSRID(ST_MakePoint(longitude,latitude),4326); But these lat/lon should be in decimal format like 33.02505 -96.70668 Is there a way/function to ...
0
votes
2answers
74 views

GeoServer create layer from PostGIS (data type point)

(Several days ago a user on gis stackexchange suggest that I should use OpenGeo (I was using geojson before). I succeed at what I was doing at that time, but now I have a different problem.) I was ...
2
votes
0answers
59 views

Broken PostGIS support GDAL

I'm having some problems with Postgres/PostGIS after rebuilding my GDAL library:( I wanted to add MrSID support in GDAL so rebuilt it with the MrSID SDK. Everything compiled ok and I am now able to ...
0
votes
1answer
40 views

Connecting to PostGIS (LATIN1) from Microsoft Access 2010 - Encoding problem?

I want to connect to a PostGIS table Using MS Access. The table has been created using the PostGIS Shapefile loader in pgAdmin. It has been encoded at LATIN1 (it wouldn't load with UTF-8 default). I ...
2
votes
1answer
59 views

Problem with matching a buffer in Openlayers and the same buffer in PostGIS query

I am using a buffer tool to create a buffer on my base map in Openlayers. In addition to creating and visualizing this buffer, I pass the center point and radius to a query. The query collects all ...
1
vote
0answers
27 views

How to define Z dimension on table with PostGIS for import in TileMill?

I'm trying to reproduce the idea behind this blogpost from Mapbox, but with other data, for example the ne_10m_populated_places_simple dataset from Natural Earth. By adding a z-dimension to the data ...
2
votes
1answer
28 views

ST_ZMax() does not exist in PostGIS

I'm trying to follow this example on Mapbox blog, about using 3D shapes in PostGIS. The database-query is this: DROP TABLE tilemill_buildings; CREATE TABLE tilemill_buildings AS SELECT ogc_fid, ...
2
votes
2answers
66 views

Suggest an algorithm to measure how a node is connected to road network

I try to measure how well a node is connected to the rest of the network. If a city has a distant suburb connected with one sole road, it's connectedness is, say 1. If it's connected by 2 roads, it's ...
3
votes
1answer
54 views

PostGIS - when I add a polygon, delete overlapping areas in other layers

I'm starting to work with PostGIS and I'd like to solve the following problem: In my database, I have multiple land use class layers, for example: "residential", "industrial", "commercial". The ...
2
votes
1answer
74 views

How to create a buffer on a linestring with varying or increasing/decreasing width

I want to buffer rivers/streams for a topographic map. I'm using a PostgreSQL/PostGIS database. Usually, I create buffer with ST_Buffer with a constant width. For example, the width of a river buffer ...
1
vote
0answers
15 views

How to SELECT one day's scene (Landsat 8 scenes)

I have a huge dataset of raster in PostGIS. Each scene is divided into tiles (tile-size 500x500). I was trying to SELECT rast FROM landsat8 WHERE ST_Intersects(rast, polygon). It runs very slow, ...
1
vote
1answer
34 views

Openlayers wfs no fid being passed from tinyows

I have a webapp - OpenLayers<->tinyows<->postgis. With 1 layer I have a problem. On localhost all works well - here is a snip of the xml I get back: <gml:featureMember> <tows:trad ...
0
votes
1answer
67 views

Import shp to Postgis using Python and ogr

I just export a Postgis Table to shp using this tips but I'm not able to import a shp to Postgis using the same library(ogr). Any idea? Thanks a lot f.
0
votes
0answers
23 views

Multiple Centroids within a dataset based on distance

Is there a way that we can find out the centroids of clusters within a dataset while differentiating one cluster from other based on distance not on any attribute value. The dataset is present in ...