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

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2
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1answer
214 views

Automated correction of parcel geometry based on area measure?

i have a set of parcels in DWG file and i have the areas that should be in these parcels in an excel file, so i have to modify each parcel to match the area specified in the excel file with a moving ...
2
votes
1answer
550 views

How do I get the closest point on a road to a point when I have imported OSM data using osm2pgsql?

I have been trying to use OSM data to find the closest point to a road for a given point. I imported the OSM data into postgis using osm2pgsql, and I am getting results back, but they are at the ...
2
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1answer
390 views

Unreachable vertex

I'm developing an application for academic purposes that mainly gives to the user a recommended itinerary for a previously introduced preferences (Gastronomy, Leisure,etc.). For this purpose, I use ...
2
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1answer
1k views

Why does my PostGIS query fail with “current transaction is aborted”

I'm trying to create a vector layer in a QGIS project using a PostGIS query. QGIS is returning the following error: Query failed 1 cursor states lost. SQL: CLOSE qgisf1 Result: 7 (ERROR: ...
2
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0answers
95 views

QGIS does not display all Features of Layer and behaves weird instead

I have a weird problem with QGIS trying to load a Layer from a Postgis Database When I open the Layer from Postsgis I have two choices: Method one: Either, I use the Panel "Browser", where I can ...
1
vote
1answer
45 views

Using negative radius buffer for ST_Buffer?

I am using postgis 2.2. I am using ST_Buffer to my polygon and it's working for positive radius (in meters) but when i am going to apply negative radius it is showing empty values. Here is my ...
1
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3answers
61 views

How can I draw the results of a PostGIS query?

Reading the solution to PostGIS > Intersect two circles. Each Circle must be built from Long/Lat degrees plus radius got me thinking. How can I graphically display a SQL query? It doesn't need to ...
1
vote
1answer
572 views

Converting from kilometers to degrees distances?

We have geometries in a Postgis database with SRID WGS84 and we have found lookups directly in degrees to be much faster than in kilometres, because the database can skip the projections I would think....
1
vote
1answer
134 views

transform MULTILINESTRINGs to curves in cartodb

I have a table with a column that contains MULTILINESTRINGs, where every string contains the longitude and latitude of a starting- and an end point, e.g.: MULTILINESTRING((97.0253024 4.3685491,8....
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3answers
245 views

How to complete the roads output of PostGIS?

I converted the file I exported from OSM to PostGIS using osm2pgsql. I have opened the table's outputs to QGIS and I saw data are not complete compare to OSM editor view. Most of the roads are broken ...
1
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2answers
1k views

Searching planet_osm_point by longitude and latitude

I used osm2pgsql to import data into my PostgreSQL database and it put gave me the following 4 tables, planet_osm_point, planet_osm_line, planet_osm_polygon and planet_osm_roads. I have looked at ...
1
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3answers
240 views

Appending data in PostGIS database with QGIS?

I 'm running postgis with qgis 2.6. I created a database and tables that i need to update with new datas provided with shapes. I cannot find how to insert them in table. All attributes both shapes and ...
1
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1answer
4k views

Modifying “pg_hba.conf” file to listen local TCP/IP conection

I am starting with PostGIS and there is an error when trying to connect through a TCP/IP connection. What I have done is: installed PostGre 9.3 in my PC, then installed PostGIS 2.3 for postGre 9.3, ...
0
votes
1answer
28 views

ST_ColorMap problem in postgis

I run into ST_ColorMap problem in postgis. Here is the code fragment: r22=> WITH sfpoly AS ( SELECT ST_Transform(ST_GeomFromText('POLYGON(( 3727069.4991851943 4256930.979258035 , 4002242....
0
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1answer
198 views

PostGIS: ST_Clip() raster in SRID:32617 with a polygon

I'm trying to ST_Clip() raster in `SRID:32617' with a polygon. What I did ST_Transform(polygon, 32617): It fails, couldn't project point() exceeded limit (-14) ST_Transform(rast, 4326, '...
0
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0answers
70 views

Converting PostGIS data to an image

I have an image showing the height information of a map. I have created a table using the 'raster2pgsql' command. This table stores the height values of the map. Now I want to create an image out of ...
0
votes
1answer
602 views

Coordinate values are out of range [-180 -90, 180 90] for GEOGRAPHY type

After import some data from OSM file into Postgre, the coordinates numbers are too big and having trouble to cast to Geography: Coordinate values are out of range [-180 -90, 180 90] for GEOGRAPHY ...
0
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2answers
708 views

Drawing curved lines in CartoDB?

I am experimenting drawing curved line from Origin to Destination in Cartodb. I was able to do so once, however, failed the second and third time. Could anyone offer me some insights into the ...
0
votes
1answer
59 views

Where to download .osm files and how to convert it to .xml? [closed]

I am new to deal with OSM data, and I want to download only .osm files not .pbf. I tried geofabrik.com but it provides .osm.pbf file format where can I download .osm files? is there any recommended ...
0
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2answers
119 views

How to implement a radius search using PostGIS

I am very new to this topic and after a long time of research I didn't find a solution. I want a query that I can use on my PostGIS database performing a radiussearch.. I inserted the Open Street Map ...
19
votes
6answers
8k views

Working with PostGIS data in R?

I work with R almost all the time, and now I am using it for doing spatial data mining. I have a PostGIS database with (obviously) GIS data. If I want to make statistical spatial analysis and plot ...
12
votes
1answer
8k views

Geocode quality: Nominatim vs. PostGIS Geocoder vs. Geocoder::US 2.0

I occasionally need to geocode >> 500,000 US street addresses (no features or intersections). I'd like to set up a geocoding service locally to handle these bulk geocodes. I've used the Tiger-based ...
9
votes
2answers
5k views

Implementing Spatial Autocorrelation using QGIS or PostgreSQL or any other free application?

I am a total newbie on the GIS scene so I hope this is not a stupid question. I have two layers in a PostgreSQL database. The first layer contains points where events happened in Europe. The second ...
17
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6answers
2k views

Spatial databases learning resources for newbies

Would be taking up a course on spatial databases next semester. Would anybody know a newbie friendly introductory resource? A vendor neutral one would be preferable. Thanks.
25
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5answers
11k views

Optimizing osm2pgsql imports for OSM data

I'm currently building an instance on EC2 on which to import the entire Planet.osm snapshot of the whole Earth's worth of data for some projects we're working on. I've spun up a large Ubuntu x64 ...
14
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5answers
19k views

How to create PostGIS template?

I am following a tutorial to install pgrouting. However, I didn't get the part when it says Start pgAdmin and create a new database based on your PostGIS template Where can I get this postgis ...
12
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2answers
4k views

What is the most common way of displaying geodata from Postgis on Leaflet?

For example, in my database I've some points with geographic coordinates. I want to display them on Leaflet JS layer. Which instruments should I use? Maybe there is some API...
12
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2answers
8k views

Spatially enabled Postgres database

I am trying to create a spatially enabled PostGIS database. I am following the PostGIS documentation, http://postgis.net/docs/manual-1.5/ch02.html#id2648455. In the short version, i executed, ...
18
votes
6answers
3k views

How do I get started with GIS Servers on Amazon EC2?

Are there any tutorials, talks or presentations that discuss the use of EC2 or other cloud computing services to host GIS Servers? Has anyone had any experience in doing it with Amazon's EC2? How hard ...
18
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1answer
4k views

Comparison of geocoding solutions (such as Gisgraphy & PostGIS 2.0) [closed]

As I am sure many of you are aware, PostGIS has finally released Version 2.0 and included within this version they have also built a geocoder (see: http://postgis.net/docs/Extras.html). Although I ...
10
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3answers
4k views

Editing PostGIS/GeoServer data via web?

I've got PostGIS installed and would like to create a web application to do some simple edits: Draw manually (over a Basemap) points, lines and polylines, using snapping points (points, end of ...
8
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4answers
2k views

What is the best web editor and server for postgis?

I'm looking for a web editor (similar to openstreetmap) that works with an map Server (postGIS). This should permit edit and create new structures on map. What is the best option? Can you help me? ...
13
votes
1answer
2k views

Identifying topological relationships using PostGIS

I'm trying to perform a basic typology analysis using PostGIS. My objective is to find any polygons that touch other polygons. To do this, I thought the ST_GetFaceEdges would work (reference). I want ...
11
votes
1answer
684 views

Nearest Neighbor Grouped Selection in QGIS

OK - so I have an interesting problem I am trying to solve. I have a list containing over 100,000 points in lat/long format which I have imported into qgis. Now, what I am trying to do here is group ...
11
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1answer
9k views

How to import KML file, with custom data, to Postgres/PostGIS database?

By custom, I don't mean a different structure of KML file, but in <description></description> section, I have data with HTML tags of this kind: <?xml version="1.0" encoding="UTF-8"?>...
8
votes
2answers
2k views

Version editing for Postgresql 9.2.4 / postGIS 2

Background: I am "building" a GIS with PostgreSQL 9.2.4 / PostGIS 2 as the database and QGIS 1.8.0 as the geographic application. There will be multiple users accessing, editing and viewing the data ...
8
votes
3answers
1k views

Poor performance with storing large rasters in PostGIS and visualising in QGIS

my question concerns the use and performance of several software tools in conjunction, namely PostgreSQL, PostGIS, QGIS, and GDAL. I'm a long-time ArcGIS, Python, and R user who is interested in ...
22
votes
6answers
5k views

PostGIS: Select features that do NOT intersect

This seems to me like such a simple question (and it probably is) yet I cannot seem to find an example that gives me the answer. Using PostGIS, I just want to select points that fall outside of ...
17
votes
2answers
2k views

Moving a PostGIS Installation

I have a simple question: I have a postGIS installation running on an old computer that I'd like to move. I spent a bunch of time playing with pg_dump and pg_dumpall without success. It seems the ...
12
votes
3answers
775 views

PgRouting - How to clip links when reaching max costs?

I have a polyline shapefile representing a road network and a second shapefile containing points. I would like to use PostGIS (presumably PgRouting) to identify sub-networks or service areas radiating ...
8
votes
2answers
3k views

Install PostGIS and TIGER Data in Ubuntu 12.04

Could someone write a brief albeit dumbed down idiot's guide to installing postgis and loading national Tiger data on ubuntu? I've tried a few guides, namely, http://wiki.bitnami.com/@api/deki/pages/...
7
votes
2answers
2k views

Automating batch load of multiple GPX files into PostGIS

I've got 50+ GPX files that I would like to "batch load" into a PostGIS database. All of the track_points data would be loaded into a "track_points" table (with typical GPS fields like lat, long, ...
15
votes
3answers
2k views

Is there a CASE Tool for modelling spatial databases?

Does anyone knows if there is a CASE Tool that would be possible for modelling spatial tables? I need to create a model and export it to SQL or a database directly. I´m using PostGIS. Thanks in ...
12
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3answers
2k views

How to speed up queries for raster databases?

I have a raster database in postgresql/postgis with these columns: (ID, rast, data_of_data). 'rast' is the column that has raster files in WKT format. An example query to find the DN value of a ...
10
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2answers
680 views

How to identify and simplify point clusters with regard to time in PostGIS?

I just started to work with spatial databases and I want to write a SQL(PostGIS) query for automatic generalizing of raw GPS-tracks (with fixed tracking frequency). The first thing I am wokring on is ...
10
votes
6answers
3k views

Should I use a CMS for my web mapping application?

For my web mapping app, I am using GeoServer as server, PostGIS as spatial DB and OpenLayers on client side (as well as other JS libraries). The map is composed of base maps and vector layers. One of ...
9
votes
5answers
2k views

Are there open source solutions for travel demand modelling?

I'm looking for open source tools for travel demand modelling (eg The four-step UTMS). Preferably in a GIS environment. That works well with Qgis, Grass and Postgis. My question is not related to ...
8
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4answers
5k views

ST_Intersection slow query

I am trying to perform an intersection between two layers: Polyline layer representing some roads (~5500 rows) Polygon layer representing irregularly shaped buffers around various points of interest ...
8
votes
2answers
2k views

Creating a spatial PostGIS table as a result of a PostGIS query

When I want to store the results of a spatial query as another PostGIS table, what should I do? I am interested in identifying all residential buildings that fall within a set of parcels: CREATE ...
8
votes
2answers
691 views

PostGIS Intermittent INDEX Performance

I have a table containing approximately 55 million data points ( point is a geometry with SRID 4326 ) and for my query I need to join this to an area table ( currently have ~1800 areas ) which ...