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

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101 views

How to Create database using OGC compliant geometries and Custom type Geometries?

I am interested in storing geometry attributes in a PostGis database, so that it would be OGC compliant, along with OGC compliant geometry types like point,line, linestring, etc. I also wanted to ...
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33 views

Automatic insert of project name into database

For every layer I've a field in my postGIS database that should be filled with the name of the current project and today I do this manually. Is there a way to do this with the Commands that can be ...
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86 views

Which is better for storage? Geometry column or varchar?

Objective: Need to store and retrieve a list of geometries from the database. Basically these are drawn by the user using OpenLayers which I would like to save and present again as a list (kind of ...
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199 views

How to import PostGIS layer with geography type to QGIS?

I tried to import in QGIS a layer from a PostgreSQL table with a geography type column created through the extension PostGIS. I noticed that QGIS doesn't seem to like the geography column... Here ...
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213 views

Different results given by PostGIS and MySQL?

I'm developing a spatial database of administrative areas. I started out with PostGIS, but as MySQL is being used in our other projects, I thought I would at least try to create a spatial-enabled ...
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174 views

Projecting PostGIS in Openlayers

I have a layer(base layer) with MultiLineString Geometries and now I need to project the layers(overlays) in the base layer from PostGIS using OpenLayers. However, I got an idea how to project table ...
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199 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 ...
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220 views

Postgresql Query Plugins Not Returning Results in QGIS

I'm using the Fishnet function as described here to create a grid. If I use the following SQL to call the function to position a grid where I want it (I'm using NZGD2000 SRID = 2193) the query ...
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164 views

Displaying text from dxf in Openlayers

I managed to import .dxf into Postgis table, and now have, among others, rows with Point geometries and values in text column (which corespodent with Label values from ACAD .dxf). What is the best ...
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81 views

MultiPolygon from database

I would like to know how to create an instance of a Multipoint from a PostGIS database.. I do the query , then got the ResultSet named "area" , the column with MultiPolygon attributes is named "geom" ...
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328 views

PostGIS: ST_Transform function conversion problem

I'm inserting map data from a GML file with srid EPSG:27700 into a PostGIS database table with srid EPSG:4326. I'm using the ST_Transform function as in this snippet: ...
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260 views

Parcel ID Mapping (brainstorming)

In my project I have a table full of residential properties by Parcel_ID. Table 2 is a TIGER streets shapefile. I would like to build a query in MS Access displaying all properties within a mile ...
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86 views

network related issues arising when running an arcpy script

Essentially I wrote an arcpy script that is within a toolbox that I ported over to a different machine to test out after the script worked locally. The script essentially utilizes the psycopg module ...
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97 views

Symbolizing Layers from a PostGIS Database to many Client Computers

I was hoping someone could help with a symbolizing issue. I have a PostGIS database on a server with a number of layers. The layers of a series of polygons, lines and points that all share the same ...
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357 views

line segments using points

Is there a way to get line segments from a linestring using points with lat/lng coordinates? ST_Line_Substring is taking float8 start/end points. Is there a way to replace the float8 with lat/lng? I ...
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384 views

Arc by center point in PostGIS does not fit the circle

I'd like to store a GML ArcByCenterPoint in PostGIS. I can work out the start, middle and end points required by the CIRCULARSTRING type and all seems to be OK, except that when I visualise the arc it ...
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29 views

Raster slightly displaced after exporting from PostGIS database

With the following queries I've exported a raster (GTiff) from my postgis database: 1.Creating a large object: WITH buffer AS ( SELECT id, ST_Buffer(geom,50) AS geom FROM ...
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43 views

How to save a google map direction into a postgresql/postgis database?

I have taken a direction(route) from google map. Can I save this resultant direction/path/route to my postgresql/postgis database? How?
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16 views

qGIS' Database Manager “Load as New Layer” Option Not Working

I'm trying to visualize some of my database queries on qGIS. I run a valid SQL query which returns a subset of my table that should be easily loaded as a layer. I then check "Load as new layer," ...
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15 views

How to set tolerance value of ST_Intersects query in TileMill?

I want to place river names in Tilemill. I use "text-dy" to displace label from the center line of a river. But for labeling polygonal rivers, names extracted from lines are used too. So at a small ...
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16 views

Problem installing Aggregate Polygons Function in PostgreSQL 9.3

I'm new to PostgreSQL and I've been trying to run a sql function written by Dr. Horst Duester, found in http://www.kappasys.ch/cms/index.php?id=65&L=5, which is used to aggregate detached ...
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34 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 ...
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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 ...
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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 ...
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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 ...
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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, ...
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55 views

QGIS loads PostGIS layers but DBManager can't connect

DB Manager can't connect to PostgreSQL, but "Add PostGIS Layer" can. My eventual goal is to save created layers to PostGIS. I assume I can do this using the DBManager Tool. I can alternatively use ...
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45 views

How to count points once with overlappying polygons?

All, We're using parcel data (polygon) to count student locations (point) based on parcel type. We're doing this using SQL and the ST_Intersects function. It works great, except the City and County ...
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33 views

PyQGIS Dialog Plugin not resetting

I have written a PostGIS search plugin that works pretty well, except two things that I just cannot figure out a solution 1) When the dialog closes and then is reopened the previous query is still in ...
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66 views

How do I catch PostGIS/PostgreSQL RAISE messages in QGIS?

I have a trigger set up in PostGIS/PostgreSQL which will show a RAISE WARNING when an inserted or updated polygon is within a certain distance of some predefined planning constraints. I want this ...
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37 views

django---error in displaying data and displaying it on the map

. i am trying to display a feature queried from postgis. . i also designed a user input field to enter the id of the desired feature to be displayed. . i have already queried the attributes first ...
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9 views

Forcing Hash Join Query Plans using PostGIS

I'm currently testing PostGIS 2.0 in a Greenplum Appliance (Postgres 8.2 based) and have hit an incompatibility between PostGIS and the MPP Greenplum environment. The basic query below can't be ...
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34 views

How can I edit spatial data automatically on postgis and check for topology errors on said data whitout using shapefiles?

So, I have spatial data stored in postgis (points, lines and polygons) and would like to edit and update those in an Open Source software (quantum GIS, grass, etc.) to check for topologic errors, ...
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45 views

PostGIS: How to distinguish overlapping routes (i.e., LineStrings) based on their direction?

I have a set of routes which are represented by LineStrings in my PostGIS database. These routes represent journeys that people make. I want to come up with routes that (a) overlap, and (b) have the ...
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32 views

PostGIS replace view crashes PostgreSQL server from ArcGIS script

I have the following script which when from ArcGIS (and a similar script from a QGIS plugin) will update a view. Every so often (around 1 in 5 times the script is run) it causes the PostgreSQL ...
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64 views

How to create a regular polygon grid in Openlayers?

I am trying to create a grid in my map and do some calculations. I seen the following links:- Create regular polygon grid using postgis Create regular polygon grid inside a polygon using postgis ...
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63 views

Traversing all possible road routes

I have created a topology from OSM data and would like to simulate a car driving every possible route along the map. The purpose is to "survey" the osm data as if in a car. My ultimate objective is to ...
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27 views

How to get intersected points between polygon and line in desired order

I have polygon for example "POLYGON((5 1, 6 1, 6 5, 5 5, 5 1))" that I want to intersect with line "LINESTRING(0 2, 10 2, 10 3, 0 3, 0 4, 10 4)" and get intersection points in the order that they ...
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81 views

pgrouting php problem “pg_fetch_result(): Unable to jump to row 0 on PostgreSQL result index 3”

I'm trying to build a simple routing web-app using pgrouting, followed some tutorial and the latest workshop. Because I'm using PostgreSQL 9.3(x64), Postgis 2.1.1, and pgrouting 2.0 so I did some ...
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24 views

PostGIS layer attribute table empty in Quantum 2.0.1

I recently installed QGIS 2.0.1 (Dufour) on a Windows 7 PC (64-bit). Today I tried, for the first time since Dufour was installed, to load PostGIS layers into QGIS. I successfully set up a connection ...
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39 views

Finding the Closest Points using ST_ClosestPoint() for MULTIPOLYGON

I am working to match between the closest points of two tables. I have two tables: Building, SchoolBuilding. Building Table: Contains Polygones, SchoolBuilding Table: contains Points (From ...
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47 views

Interpretation of PostGIS geocode function ratings

Edit: I am using Postgres 9.2 and recently installed PostGIS along with the Tiger Geocoder from the extras folder and downloaded all the latest Tiger data. I have been testing the Tiger Geocoder ...
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30 views

Create a single line from a resultset of line segments

How can I create a single line using the line segments geometry found in each row in resultset? I followed this tutorial: http://anitagraser.com/2013/07/06/pgrouting-2-0-for-windows-quick-guide/ I ...
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86 views

Need to enhance a function for creating quadrants within polygons

I wrote a function that creates arbitrary quadrants within a polygon SELECT (quadrant(20,0.0,90)).* The first parameter is the polygon ID, the second one is the start angle and with the third one ...
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43 views

Trajectory Indexing: How could I store and index the large trajectory dataset generated by cars' GPS?

I have a large trajectory dataset generated by cars' GPS. Since I will do some data mining work on them, I need an efficient way to store and index them. I read some papers about Trajectory Indexing ...
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145 views

Creating a spatial database using EXTENSIONS: error loading legacy.sql

I am using Postgres 9.3 and PostGIS 2.1, installed in a Docker container via RUN echo "deb http://apt.postgresql.org/pub/repos/apt/ precise-pgdg main" >> /etc/apt/sources.list RUN apt-get -y ...
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51 views

PostGIS Raster: raster2pgsql was not found in /usr/lib/postgresql/9.3/bin

I have installed sucessfully Postgresql-9.3-postgis on Ubuntu 12.04, following this instructions: http://trac.osgeo.org/postgis/wiki/UsersWikiPostGIS21UbuntuPGSQL93Apt Having done that, I have ...
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53 views

Complexity of A-star algorithm using pgRouting in a graph

I'm using the A-star algorithm in pgRouting. It uses the Manhattan distance as a heuristics ((|dx|+|dy|)/2). What would be the time complexity in a standard route network? Based on Why is the ...
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114 views

Write Nominatim-like geocode query using only PostGIS functions?

I'm new to PostGIS and was anticipating being able to write geocode queries using only the functions provided by PostGIS. However, once I loaded my database using osm2pgsql and discovered tables like ...
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96 views

identify subgraphs within planet_osm_line table

I want to identify subgraphs within the planet_osm_line table of the osm2pgsql-schema. those subgraphs are classified by certain tags i want to check. My first attempt was to do this recursively with ...