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

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1answer
57 views

ST_INTERSECT of each element of two tables (polygons, lines)

Im new to postgis and trying to solve the following problem: I have two tables: 1. containing polygons 2. containing lines I need to find out the id of all polygons on each line and fill them in new ...
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22 views

How to get correct measure with PostGIS SQL query? [duplicate]

First of all, sorry my bad english. I am new at gis. So I want to measure my road. I want to use measure unit kilometers. But I am a bit confused. I have a garmin etrex gps device. So I get my ...
0
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1answer
37 views

Finding lines of similar attribute with respect to nodes connected to its both Ends

I have line networks with node generated for Start and End Point . how to check if a line has correct attribute with respect to point created at its End. for instance FuID_Line = ABC_BDQ and Start ...
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3answers
54 views

How to append 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 ...
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0answers
15 views

From Openlayers 2 report generation

Can u suggest how a JasperReport can be geneated by an user accessing an point (say a wireless tower in map) on a active layer done in openlayers 3. Here the architecture uses openlayers 3 and is ...
0
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1answer
37 views

How to find routes between for each entry in a list of point pairs?

I have a postgis database with two tables. In the first table I have linestrings of a street network. The second table has points that are located on the street network. What I want is to find the ...
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0answers
19 views

How do I step into the C++ functions from an external Python app I'm debugging?

I just wanted to see how to step into the C++ class QgsVectorLayer()'s methods from the python call to QgsVectorLayer(self.uri.uri(),'foo','postgres'). I'm trying to debug and it trying to step into ...
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28 views

ERROR IN sudo PGUSER=postgres make installcheck step

I am trying to setup cartodb on Ubuntu 14.04. I installed all the dependencies & requirements. Postgres 9.3 and postgis 2.0 are also installed. Whenever I try to execute following Steps : ...
2
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1answer
50 views

Symbolising null features in graduated symbology

I have a polygon feature dataset, and an attribute from a different table that I join (one-to-one) within QGIS in order to symbolise the attributes as a choropleth map. However, not all polygon fields ...
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67 views

Removing pseudo nodes from PostGIS database using ST_ModEdgeHeal()?

I have used osm2po (5.0.0) and its autogenerated SQL file to load some 25% of Europe.osm.pbf as a network table into my PostGIS database. I have also created an associated nodes table with select ...
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31 views

Routes through centroids and array functions

I have a table stopcentroids4 like in figure with the following fields: gid, routes, geom and i want to draw a line for each route that runs through centroids. In my code there is a mistake. ...
0
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1answer
54 views

pgRouting cannot find extension control file

I am trying to use pgrouting on OS X. I installed the following: brew install postgres brew install postgis brew install pgrouting When I try to create the extension pgrouting I get the following ...
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82 views

How to create projects in Tilemill Ubuntu Web service?

I have set up Tilemill on a Ubuntu server and successfully accessed it from browser using TILEMILL_HOST:20009 I have already uploaded planet_osm data to postgresql/PostGIS DB in the same server ...
7
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1answer
199 views

How to visualize measure values along linestrings in QGIS?

I have a series of LineStringM geometries. The measure value represents slope (or stream gradient) at each point in the geometry. I love QGIS's robust styling options, but I can't find a way to render ...
0
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1answer
12 views

Combine Elevation Raster and MultilineString to create MultilineStringZ in PostGIS

I want to show how steep a given stream is. I'm using PostGIS and QGIS. I do not have access to ESRI products. I have some ideas, but I'm not entirely sure how to proceed, and some of my assumptions ...
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0answers
28 views

Generate polygon from html

I would like to generate a polygon using Postgis - pgRouting ( osm_network ) + Geoserver ( Sql code) + Html5 . I Have followed pgRouting workshop r5 tutorial to get shortest path between two points ...
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0answers
36 views

How to select main cities in a country from planet OSM data

I am trying to create a map with my own style with the help of geoserver and planet OSM data,but trying to give style to the polygon at different zoom level ,need to highlight main in cities in ...
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0answers
66 views

PostGIS: snap latitude/longitude input to nearest OSM road point

I need a function to return the nearest OSM road point for any latitude/longitude. i.e. users input a latitude/longitude and postgis finds and uses the point on a road that is the nearest to it. ...
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1answer
56 views

Drawing routes through centroids

According with this link http://workshops.boundlessgeo.com/postgis-intro/advanced_geometry_construction.html I'm creating lines that describe routes. I have a table stopcentroids4 like in figure with ...
2
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0answers
39 views

pgrouting librouting.dll library is supposedly missing when it is not

Yesterday, I successfully installed pgrouting from the most recent x64 2.0.0 binaries, at least this is what I thought. I was able to perform first query - select pgr_createTopology() from the ...
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2answers
35 views

How can I add extensions to PostGIS?

As newbie with PostGIS, I downloaded Postgresapp for macosx. Everything works fine, but I noticed some differences with Stackbuilder which adds to extensions address_normalizer and grouting. Can I add ...
0
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1answer
47 views

Distance between a Point and Linestring: PostGIS/GEOS vs. Boost

I am currently using the GEOS library through OGR and data from a PostGIS database to work with geospatial data. I now found myself in the need to use some of the algorithms Boost.Geometry and ...
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1answer
22 views

Checking if point is within multipolygon using ST_Contains?

Why is this query always returning false? SELECT ST_CONTAINS(the_geom,(select ST_GeomFromText('POINT(26.8715 80.7799)'))) FROM blockgeom Can I not check if a point is within a multipolygon using ...
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0answers
18 views

How to transform isolines to isopolygons with postgis?

I have a table a postgis table of isolines that's defined like this: CREATE TABLE myisolines ( gid serial NOT NULL, isotime timestamp without timezone, val numeric(10,4), geom ...
1
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1answer
40 views

How to create postgresql triggers to calculate geometry from x,y and vice versa at the same time

I have a postgis table with point geometry which looks like this CREATE TABLE mypoints ( gid serial NOT NULL, coordid integer, geom geometry(Point,4326) ); And a table with coordinates ...
0
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1answer
40 views

ST_AsGeoJSON function slow in PostGIS

I'm currently trying to pull neighborhood data from Zillow's Neighborhood page (http://www.zillow.com/howto/api/neighborhood-boundaries.htm) and then load it onto a leaflet map, openstreetmap. I ...
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1answer
47 views

how to Find nearest line for the given point from a collection of lines?

I have table with lines(linestring).For a point wich i give it , I want to find out nearest line in point. I almost developed a query, but it is return the same line every point i give. the query ...
0
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1answer
28 views

geometries with different SRIDs errors (even after setting SRID)

I've looked at existing questions about this (including this one) and followed the advice that was shared there. I'm still seeing this when I run some queries: RuntimeError: Postgis Plugin: PSQL ...
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2answers
43 views

Querying PostGIS and OSM to get only major stations and subway of UK?

I am working with Great Britain OSM data. I have read the classification of UK railway stations. There are a lot of classes in there such as subway entrance, halt, station and many others. I want to ...
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0answers
62 views

box2d spatial type

I'm storing data that defines a box. I created a column by adding it to my table as follows: SELECT addgeometrycolumn('grid', 'grid_geometry', 32650, 'GEOMETRY', 2); I then insert my data in using ...
0
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1answer
94 views

PostGIS: Ensure Intersection of 2 Polygons results in a Polygon

I want to ensure that the result of ST_Intersection(polygon1, polygon2) is also a polygon. I initially filtering by ST_Overlaps(polygon1, polygon2) but that seems to only ensure that both features ...
2
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1answer
68 views

PostGIS cannot create new feature

I have a PostGIS database - using the main user I can create/update new features no worries. I have created a series of new logins and given them all full access to select/insert/update etc all the ...
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21 views

Ways of editing Postgis tables from remote desktops (WFS?)

I've got like 500 postgis tables and i would like to serve then as WMS and especially as WFS to be able to edit that info. To do so i read that the easiest way is Mapserver + TinyOWS. Mapserver works ...
2
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1answer
40 views

PostGIS replace pixel value by lookup table?

I was wondering if it is possible to write a PostgreSQL statement to replace the value of each pixel in an input PostGIS-raster with a value obtained from a look up table. For example, suppose I have ...
2
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0answers
21 views

Geoserver : create a rasterized polygon / dynamic fill for polygons with features from database

I decided to post here because I couldn't find any answer to my problems on the internet. So I am using geoserver 2.7-SNAPSHOT, everything is working fine but I need to implement a new function or ...
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0answers
30 views

Postgis routes diagram point-to-point

I have a set of centroids to which are related a set of points characterized by linename. The table with the points contains these fields: id ¦ linename ¦ lat ¦ lon¦ I would like to make a diagram ...
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0answers
71 views

PostGIS: Merge any and all adjacent polygons

I would like to do adjacency tests on a parcel (polygons) layer and merge them if they fit certain criteria (could be size). Per the picture below, I would like to merge polygons 1,2,3 and 4, but not ...
3
votes
1answer
38 views

Finding all segments that makeup a road in OSM

I've spent 2 days trying to figure this out and I'm afraid that it's something that's not possible. If that's the case then I'm thinking the wrong with with respect to OSM data. Let's say I have a ...
0
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0answers
46 views

How to speed up raster/map algebra in PostGIS?

I am testing map algebra with PostGIS (2.1 with PostgreSQL 9.3) on two images, and found it to be rather slow. For example, dividing two images of 7200 * 3600 pixels took 110 ~ 120s on a desktop with ...
2
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2answers
62 views

How to encode a point geometry in Geojson?

I have point geometry in posgresql which I query as follows: select ST_AsText(geom) as pointgeom from pointable. I'm using python as server side script. I want to pass the result as Geojson response ...
0
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1answer
13 views

ST_MakeEnvelope vs casting BOX as box2d

When I'm filtering by bounding box, I've found that I can either do SELECT id, the_geom FROM my_table WHERE the_geom && ST_MakeEnvelope(minlng,minlat, maxlng,maxlat); as well as SELECT ...
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2answers
25 views

Learning pg_routing - shortest_path error

I'm learning PostGIS and pg_routing to help in our project planning and grant applications at my transportation agency (we wanted to move beyond the limitations of the 1/4 mile walking buffer we use ...
2
votes
1answer
36 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 ...
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0answers
58 views

Create GeoServer SQL View with variable number of arguments ( double precison [ ] )

I was trying to create a PostGIS procedural function which will perform a particular operation depending upon the user's provided coordinates. But since the user can provide any number of coordinates, ...
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3answers
118 views

Plotting Geo Points with “by arc centered at” Instructions

A recent Supreme Court decision redefined the legal boundaries of California along the Pacific Ocean: http://www.theverge.com/tldr/2014/12/15/7397085/supreme-court-california-boundaries-map I am ...
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28 views

How can I prevent ogr2ogr from trying to get the SRID from PostGIS?

I'm running ogr2ogr for a PostGIS to GeoJSON export like this: ogr2ogr -s_srs EPSG:4326 -f GeoJSON unique_geoms.json "PG:host=localhost dbname=local_data user=local_user password=local_pass" -sql ...
3
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2answers
55 views

pgrouting - network distance many-to-one shortest paths

I want to find the distance (km) between each origin point to the closest destination point (restaurants) using pgrouting. I have 3 tables my road network with nodes and edges 140 origin points - ...
2
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1answer
57 views

osm: relation tags to nodes

I filter an osm planet extract using osmfilter. I am only interested in nodes belonging to route=subway relations. After performing this operation, I use osm2psql to load all the data into my postgres ...
2
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0answers
35 views

filling the attributes according to intersection of two layers (Postgresql)

How to automatically fill attributes of a point layer according to the exact position in the polygon layer? I mean how to write a command in PostgreSQL to automatically fill the attributes by the ...
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0answers
29 views

PGeo: MDB Tools driver not found

I'm trying to load a Access .gdb(.mdb) database into postgis using ogr2ogr. I'm running Ubuntu 14.04 with gdal 1.10. I've install both unixODBC and mdbtools as per the instructions at ...