Version 2.0 of PostGIS brought a heavy set of new extensions for the PostgreSQL object-relational database, adding greater support for spatial objects.

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How can I associate a consistent polygon area with a set of attributes using a topology?

Consider the following topology. SELECT CreateTopology('topotestschema', 0, 0.01); CREATE TABLE topotest (id SERIAL PRIMARY KEY, data TEXT); SELECT AddTopoGeometryColumn('topotestschema', 'public', ...
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171 views

Determine PostGIS geography polygon orientation

How can you determine the orientation of a PostGIS geography polygon? I'm looking/hoping for a function that would tell me which side is the interior (left or right) as you traverse the vertices of ...
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2answers
2k views

Problem with running PostgreSQL 9.3 after installing pgRouting

I have PostgreSQL 9.3 installed on the server. It worked just fine. I also had a webservice which connected to a database. That also worked like a charm. Later, I decided to install and use pgRouting. ...
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1answer
315 views

raster2pgsql does nothing

I try to load rasters through raster2pgsql. I try to call it through pgAdmin command line, but when I call any raster2pgsql command (even raster2pgsql -G), it does nothing, I just get another line to ...
3
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1answer
514 views

PostGIS: ERROR: lwpoly_from_lwlines: shell must have at least 4 points

I have achieved to close lines in order to build a polygon with: st_addpoint( st_makeline(geom ORDER BY .cd_noseq), st_pointn( st_makeline(geom ORDER BY cd_noseq), 1) ) but ...
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1answer
74 views

Implementing Wrapper of PostgreSQL?

How can I implement the Wrapper of PostgreSQL? I found this useful looking wrapper from a FOSS4G routing with pgRouting Workshop but I do not know how to implement it!
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1answer
117 views

postGIS: what is more efficient: single or two-point search

I have seen different approaches to conducting searches. Which is the best approach in storing the data for database efficiency: saving both longitude and latitude points longitude latitude vs ...
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2answers
179 views

problem merging polygons based on a column value - using Spatialite

edit: as I am unfamiliar with any tools I decided to try my luck with PostGis. I imported my data. and executed the query : create merged as select delomrade_code, st_union(geometry) from grunnkrets ...
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1answer
173 views

Binary insert into Postgis geography column results in value being inserted as geometry

When writing WKB as a value (and as a binary parameter) to a geography column, the persisted value is not geography. Example Java is also available here: ...
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1answer
73 views

Local Coordinate System

I am currently evaluating the use of PostGIS (version 2.0) for: a project that will store 3D coordinates (x, y, z) data the data will have it's own local coordinate system which does not correspond ...
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1answer
214 views

Routes Consult with pgrouting / openlayers [closed]

I'm starting with pgrouting. After suffering a bit unable to put the data in osm postgis using osm2po with the excellent tutorial http://anitagraser.com/2011/12/15/an-osm2po-quickstart/ ran the sql ...
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1answer
45 views

Not empty geometry having blank text

i'm having problem with geometry column, for some rows i have geometry with blank text, this query will describe more the problem : select geom, ST_AsGeoJSON(geom), ST_Isvalid(geom), ST_IsEmpty(geom) ...
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1answer
34 views

Expression with postgis

I'm using mapserver and PostGis and I want to draw a geometric table in mapserver. The trouble is when I connect mapserver to PostGis and I want to draw the objects but in different colours. I mean I ...
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2answers
282 views

UpdateGeometrySRID and ST_Transform are the same thing?

UpdateGeometrySRID actually transforms the coordinate system of my data? For in the PostGIS documentation it appears the trim ST_Transform (Returns a new geometry with its coordinates transformed to ...
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0answers
196 views

Function ST_Transform postgis 2.0

I've read many forum posts on the function ST_Transform but unfortunately was unable to resolve my doubts so I posted a new question. I have a spatial table SRID = 101010 and want to transform it to ...
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1answer
106 views

Empty geometry resulting from pgrouting function

Let me start by saying I'm assuming I'm missing something very silly but I can't see it. I have a table of points and I'm trying to generate a polygon around each point that estimates a maximum of ...
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2answers
387 views

Find out whether geography point lies within geography bounds

I have three points: Point A Point SW Point NE I want to know if Point A resides within the bounds determined by points SW (for south-west coordinates) and NE (for north-east coordinates). I've ...
3
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1answer
428 views

Is there any random data generator supporting geometry in PostGIS?

I found few random data generators for PostgreSQL (such as this one), but none supporting PostGIS geometry type, other than point. Making points would be quite easy, but for lines with multiple nodes ...
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3answers
833 views

ST_transform postgis

SQL within that zone is a point SELECT "public".zona.zts FROM "public".zona WHERE ST_Within ( ST_Transform ( ST_GeomFromText ( 'POINT(-30.033514 ...
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1answer
534 views

How to have PostGIS 2.1 and the Python osgeo library installed together without compiling from source?

My python application makes heavy use of the osgeo library. We're looking to upgrade from PostGIS 1.5 to PostGIS 2.1, and I'm having issues. I'm installing packages from the Ubuntu GIS PPA. Before, ...
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0answers
83 views

rasterize a geography polygon using postgis 2.1

I am still bit new to Postgis 2.1. I am trying to rasterize a polygon, meaning that I have a polygon of Syria and I want to create an empty raster that contains the shape and geography reference of ...
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1answer
138 views

Break line into 100m segments

I have a line geometry in PostGIS and I am wondering how I would break the line into 100m segments. Is there a function for this?
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1answer
204 views

How can I find the segment of a line that lies within a polygon using Postgis?

Given a "road", represented by a line, that crosses a "state", represented by a polygon: What is the SQL query I can use to find the segment of the road that is within the state? A concrete example. ...
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2answers
170 views

How to select the cross streets in postgis spatial table?

I've used ST_Intersects and ST_Crosses but between two different tables. I have a table of streets and intersections want to know them. For example select all streets that cross the Street A. Can ...
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1answer
62 views

query to get predicted location after traveling on pgrouting route for some hours, postgis 2, postgresql 9.3

I am using Postgis 2.0 on Postgresql 9.3 on Ubuntu 14.04 x64. I am trying to find an efficient way to fulfill this routing request. So I am able to get the shortest route using the source and target ...
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0answers
541 views

how do I create a RESTful PostGIS web Service Framework?

I have PostGIS tables that store vectors that want to show on Google Maps. Read the post http://gis.stackexchange.com/questions/22354/how-to-display-a-postgis-table-on-google-maps But one thing that ...
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0answers
62 views

Import raster to postgis and add a foreign key constraint

I use raster2pgsql to import raster files into a table with this command line: C:\Program Files\PostgreSQL\9.3\bin>raster2pgsql -s 4326 -M -F -a c:\temp\mun.tif public.basqui_raster | psql -U ...
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3answers
71 views

PostGIS2 have automatic BBOX indexing?

I need to compare millions of geometries by the && operator (BBOX). When CREATE TABLE see geometry type on PostGIS2, it do also something like INDEX ON t USING GIST(g)? or I need to express, ...
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1answer
194 views

Get latitude and longitude of each point forming a MultiLineString

A MultiLineString is formed by a sequence of points and each point has latitude and longitude. Use the sql below to get the latitudes and longitudes of each point so that my MultiLineString: SELECT ...
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1answer
311 views

how to build and install pgrouting-2.0 on postgresql-9.3 on ubutntu 12.04 Lts precise?

I try to build following instructions from this link https://github.com/pgRouting/pgrouting after downloading from the github. I have done the cmake command and there is my error output: ...
2
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1answer
98 views

PostgreSQL : how do I make this sum [closed]

I have this huge table with all the addresses of my country in it. Every house is an object, and there is a column for the streetname (or street ID) and a column for the housenumber. I want to make a ...
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2answers
74 views

How can I speed up these queries

I am trying to make some calculations using PostGIS and PostgreSQL. There are 3 important tables : wbn, wgo and wvb. These tables have about 500.000 objects in them (geometries). The problem is that ...
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109 views

PostGIS 3D Extrude function

I selected buildings from OSM (which represents my city). I insterted a new column 'height' and I filled with a random number exactly number 2, so every building have 2metres altitude. Buildings are ...
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1answer
152 views

3D functions with SFCGAL in PostGIS

I have this setup: "POSTGIS="2.1.2 r12389" GEOS="3.3.8-CAPI-1.7.8" PROJ="Rel. 4.8.0, 6 March 2012" GDAL="GDAL 1.9.2, released 2012/10/08" LIBXML="2.7.8" LIBJSON="UNKNOWN" TOPOLOGY RASTER" on ...
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2answers
77 views

Do I still have to use a template DB for PostGIS?

createdb mydb -T template_postgis Is this -T template_postgis still necessary in new versions of PostGIS? I never saw this db being different, it always has those 3 sql files you run there. Is this ...
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1answer
265 views

ST_Union to merge tables containing lines?

I have to build a street network with Postgis that will be used with pgrouting. I have two tables: 1) the_network (182 lines): is a MULTILINESTRING table. Having columns road_name (varchar) / ...
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1answer
59 views

Trying to understand / troubleshoot intersection behavior of postgis

I'm trying to calculate the percent of intersection between two polygons using postgis. I was able to do so successfully for 90% of my polygons, but about 1500 have very unexpected values. I ...
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1answer
66 views

Weird ST_Contains behaviour

I'm creating a polygon and then checks whether one of the origin points is contained inside the polygon. To my surprise, I get False (?!) What is wrong here? SELECT ST_contains(ST_GeomFromText('POINT ...
3
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1answer
1k views

Improve speed of PostGIS “nearest neighbor” query?

One of the features of the Python/Django/PostgreSQL web application I'm building is that a user will be able to see the 100 other users who are nearest to them, sorted by distance. I'm using PostGIS ...
2
votes
1answer
484 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 ...
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1answer
47 views

PostgreSQL : question about SELECT .. WHERE .. = max()

If you have, for example; SELECT * FROM data WHERE line = min( (SELECT length FROM lines) ) AND number < 500; (It's just an example, not a real code) How does PostgreSQL react when the ...
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1answer
89 views

Postgis query not using the spatial index

I've been using postgres8.3/postgis1.5 for some time, and it works well. I've moved my entire database to a new, faster machine and upgraded to postgres9.3/postgis2.1 using pg_dump/postgis_restore.pl, ...
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0answers
617 views

Problems moving POSTGIS database from postgresql 8.3 to 9.3 using Navicat

I am using Navicat 11 to move a POSTGIS database from 8.3 to 9.3 on Mac OS X 10.9. I have installed PostgreSQL 9.3 and PostGIS with homebrew (brew install postgresql postgis) and everything looks ok. ...
2
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1answer
227 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 ...
4
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1answer
479 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 ...
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3answers
1k views

How to create random points in a polygon in PostGIS

I have a polygon layer, and would like to generate random points in each polygon. An initial searching in Google resulted this website which presents a function for this purpose: ...
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3answers
216 views

Geometry vs geography for line-to-polygon intersection

I have two WGS84 NAD83 shapefiles, one polygonal, the other containing lines: Geometry: Polygon Feature Count: 1294 Extent: (-79.761059, 44.991143) - (-57.105486, 62.582865) Layer SRS WKT: ...
1
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1answer
127 views

ST_AsLatLonText returns wrong data

I want to list all cities in lubelskie vovoidenship, which is relation 130919. I also want to get latLong data for each city. To perform this I do: SELECT name, ST_AsLatLonText(way), place ...
1
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1answer
123 views

Problem with runing a loop in a query in PostGIS

I am new to PostGIS and I have a question which can't solve. I have a table of buildings each having a value for number of people living in it. I would like to calculate the total value (sum of number ...
2
votes
3answers
188 views

Problem with result of query in PostGIS

I run the following query and irrelevant of the point coordinates and radius I always recieve all the records of the table I'm querying. Can anyone point out what the problem could be with this query? ...