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

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35 views

ArcGIS resampling rasters by maximum pixel value?

I need to resample a binary image of linear features like roads, rivers to a coarser resolution, conceptually combining multiple pixels into a single one. 1 indicates presence of the linear feature, ...
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37 views

Speeding up PostGIS ST_AsGeoJSON

I am writing a query that would give me the geojson element contains the outline of a US State along with some additional information. The problem I am running into is the function ST_AsGeoJSON from ...
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40 views

How to use a PostGIS sequence in QGIS editing session?

I can't seem to get the sequence on my PostGIS table to increment to NEXTVAL in a QGIS editing session. My PostGIS table is defined as: CREATE TABLE qgis_topology_editing_test ( geom ...
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1answer
77 views

Trying to bind pop-up in leaflet via GeoServer GetFeatureInfo. Is there anything wrong in my code?

Simple Leaflet Map <script src="js/leaflet.js"> </script> <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script> ...
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23 views

Display graduated QGIS buggy?

I counted points in polygons in PostGIS like this UPDATE hexagons SET count = (SELECT count(*) FROM points WHERE ST_Within(points.geom, hexagons.geom)); That came back with that UPDATE 1554 That ...
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29 views

load raster (geotiff files) to postgis with url

I tried to load rasters to postgis with raster2pgsql but this not satisfy my project because it uses local files. i have 5000 and will be more in future geotiff files in cloud host. is it possible ...
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1answer
57 views

“Get” results of PostGIS [closed]

I am getting warm with post PostGIS. I am working in the Command Line. What I am wondering is how do I "get" the results of PostGIS. So imagine I have this select name, neighname from neighborhoods ...
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1answer
23 views

Parameterizing Postgis function in GeoServer's SQL Views

I have a problem when parameterizing a postgis function in sqlviews If i create this sql, all works like a charm attaching this &viewparams=idvia:6753 to the url SELECT ...
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67 views

spatial query using GeoExt and openlayers

I want to allow the the User to make advanced custom queries against a layer.So he can search by name or another attribute and get zoomed to the requested feature ( hospital in my case) . I m ...
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1answer
37 views

Raster and Geometry ST_Intersects slows when add buffer in PostGIS

I have a table containing rasters for the whole of the UK, the below query is very fast (0.1 seconds) and gets all of the rasters that are intersected by the line between a start point and an end ...
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1answer
31 views

SLD styling rule for first and last geometry feature in PostGIS table

Writing a SLD file to style a Points layer which I publish as WMS with GeoServer, is it possible to specify a rule that is only applied to the first and last features in the underlying PostGIS table? ...
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1answer
64 views

Is there any method to retrieve SQL queries into a GeoJSON file using JSP?

I want to display the contents of my PostGIS database of various shape-files in leaflet pop-up dynamically. I know there are static methods available that retrieves attributes. But I need to by ...
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95 views

I have not found shp2pgsql in postgis installation

I have been installed postgis following this guide. All is OK. SELECT postgis_full_version(); "POSTGIS="2.1.7 r13414" GEOS="3.4.2-CAPI-1.8.2 r3921" PROJ="Rel. 4.8.0, 6 March 2012" GDAL="GDAL 1.10.1, ...
0
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1answer
98 views

How to bring my PostGIS map from GeoServer to Leaflet based web application?

I have created a group of shape-files using QGIS and I have stored their corresponding information in PostGIS database by importing the shape-file into pgAdmin3 using shape-file and DBF loader. Then I ...
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1answer
48 views

How to fix “Detected out of bounds geographic extent”

I hope someone can help me to solve this problem. i want to make a map with TileMill v.01, when i try to add layer using shapefile (i use QGIS to edit *.shp file) or postGIS i always get error ...
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2answers
45 views

Create point on a line with given distance from end in PostGIS

Does anyone know how to create points along a line (MultiLineString geometry) with a given distance in PostGIS? I'd like to create points at a regular distance over a line, which represents a ...
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38 views

Method to translate PgRouting to ESRI Network Analyst network dataset?

I have a network dataset in a PostGIS database that is set up and routable via PgRouting. I would like to take this dataset and import it into Network Analyst in ArcMap in order to make some ...
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39 views

Server-side map generation from postGIS database

I have loaded some OSM data into a postGIS database, using imposm. Now using this data base, I computed a value associated to every point of the map (could be anything, real-estate average price or ...
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38 views

OS Terrain 50 into Postgresql/PostGIS for lat/long analysis

I am performing analysis using line of sight's and followed a very useful blog post at http://davidrowley.blogspot.co.uk/2013/08/calculating-line-of-sight-with-postgis.html which detailed how to load ...
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1answer
33 views

Error when creating new view using ST_Union (PostGIS)

I have a table in PostGIS (2.1.7) containing adjacent multipolygons, and I'd like to create a view containing polygons which are merged versions of the multipolygons based on some field value. I ...
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2answers
87 views

Why the execution of a query is very slow using PostGis?

I'm applying this Query to 8257800 point but it's taking 15 hours and it didn't return a results. SELECT a.gid , b.gid, st_distance(a.geom,b.geom) FROM shp1 a, shp2 b where ...
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25 views

Cannot draw geometery on WorldWind

I'm trying to draw my geometery on worldwind but it keeps saying WARNING: Unspecified coordinate system and draws a default blue line in the middle of nowhere. The procedure is that I populate ...
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1answer
37 views

how to insert area of polygon into a column named area in a polygon map in cartodb?

SELECT ST_Area(the_geom) FROM cartodb_query gives the area but trying to insert it into an area column using: UPDATE cartodb_query SET area = ST_Area(the_geom) doesn't work.
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68 views

where to download gdal_polygonize.py?

I am trying to help out a friend of mine. She learnt GIS in school in the past using ArcGIS but has recently installed QGIS package on her Mac OSX. When she tries to render raster into shape file, ...
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22 views

Need to find polygon info from postgis

After importing shapefile into postgis I got geom data as MultiPoligon Like: ...
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1answer
43 views

Postgis 4D Range Query

Is it possible to express a 4D range query in Postgis? I would like to know what 4d points lie within a hypercube. This is my table: CREATE TABLE myTable ( point geometry, attrib ...
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1answer
49 views

Create blank table from unix shell

I am in the middle of trying to create my first PostGiS database and seem to be running into problems developing scripts to automate importing the various spatial formats so I can use them in my ...
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1answer
89 views

Can I identify if a point is inside a volume in PostGIS?

We are currently investigating PostGIS as an option to look up three-dimensional blocks which contain a point (and later also lines). At this point in time I cannot see any functionality that operates ...
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1answer
37 views

In PostGIS, why does ST_Covers return f on this query?

In general this query functions fine. In my PHP application I tested it with a large number of points, and they all seemed to be true or false as appropriate (when I pasted data into two online WKT ...
6
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1answer
174 views

PostGIS polygon edge analysis (orientation, edge length)

I am rather new to the world of GIS and especially PostGIS, so please excuse me if the answer seems evident... I would like to do analysis on a number of buildings. One thing I am interested in is ...
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1answer
25 views

Fail to display correctly newly inserted data in PostGIS on Geoserver

I have created a postGis store in Geoserver. I have created layers with points and lines and I display them on an OpenLayers based application. I also use an FME workflow to insert new data to my ...
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29 views

Getting connected points in intersection from OpenStreetMap using PostGIS?

I'm trying to get the points that connected with the intersections. suppose that I know the point of the intersection (if we see in the pictures, I represent the intersections as black node). Now ...
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1answer
43 views

Query table names

I want to query a table in my postgis table named Seg_060_2009 using psycopg2 and cant seem to get my query to execute. The query will execute if I name the talbe layer. Are there restrictions on ...
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1answer
38 views

Loop through table, look for word in text field, set boolean true if word exists

I want to create a function that loops through a table and checks if a specific word exists in a text field. If it does, the function should set a Boolean field true. This is what I've come up with. I ...
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54 views

Splitting lines table using point table in PostGIS

My problem is that I want to get the shortest route between multiple point pairs which are stored in a table (PostGIS). In PostGIS I also have a network created using pgr_createTopology on a table ...
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1answer
50 views

Spatial join points and polygons in PostGIS

I have two spatial data sets in PostGIS tables: polygon grid (table: grid_jakarta) points (table:tweets) For each point in 'tweets', I want to retrieve the reelvant attribute 'gridID' from the ...
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1answer
22 views

Creating network for pgRouting from set of multiline strings?

I have a table which is a set of multiline strings. I wish to create a pgrouting topology from that table so I can do shortest-path problems. I have tried pgr_createTopology but it failed. Is ...
0
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1answer
44 views

How to create a polygon from the union of the areas formed by a circle running in a line formed by two geographic points?

How can I create a polygon like in the right side of the picture from a line formed by two geographic points like in the left side of the picture in PostGIS? I was thinking in calculating the area ...
0
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1answer
69 views

Database queries using GeoServer? [closed]

I am new to GeoServer. I have a PostGIS database and GeoServer setup. How can I query the database using the GeoServer/ Boundless SDK? I have OpenGeo Suite 4.6 and I am trying to query the database ...
2
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2answers
111 views

Merging linestrings in QGIS using PostgreSQL and PostGIS

I've to merge all linestrings from a PostgreSQL table "river" where not more than two start-/endpoints are overlapping. In the illustration below I use a "M" to mark all linestrings that needs to be ...
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38 views

Can't create ArcGIS feature class with PG_GEOMETRY keyword

I have enabled a PostgreSQL database as an enterprise geodatabase with ArcCatalog 10.3 (using server license file etc). When I create a new feature class with PG_GEOMETRY keyword, I get an error: ...
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2answers
54 views

How can I check if all boundaries of a polygon coincides with one or more of a set of lines

I have a polygon shapefile, and theoretically, all features in the shape are bounded by the union of some lines in another shapefile. Is there any way to confirm if this is true? I'm using QGis, FME ...
2
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1answer
100 views

How to efficiently use a Postgres DB with Python

I have a Postgres DB with a lot of lines that are too long and so now I want to split those lines into smaller ones. This is why I started writing a little python script for that job. Basically it ...
0
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1answer
54 views

GeoServer namespace URI causing invalid WFS transaction requests

Is there any naming conventions with GeoServer's namespace URI/settings that need to be changed to allow their proper use? I have a WFS-T that is being edited in QGIS - after a lot of issues getting ...
0
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1answer
114 views

How to set up wfs-t service in Geoserver using openlayers from postgis data?

I published my postgis data layers into Geoserver. I have enabled wfs in the edit workspace > services. Still the "layer preview" does not show any options under wfs. See the image. How can we set up ...
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25 views

pgRouting pgr_trsp returns no route

Installed a fresh PostgreSQL v9.4.1 x64 on Windows, and used the Application Stack Builder to install PostGIS 2.1 bundle which includes pgRouting 2.0. I created the sample data ...
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1answer
29 views

Can OpenGeo Suite co-exist with Homebrew-installed PostGIS/PostgreSQL in Yosemite?

I installed PostgreSQL (9.4.1) and PostGIS (2.1.7) using Homebrew in Yosemite (10.10.3). I'm just starting my way through "PostGIS In Action." I've been starting and stopping the server in Terminal ...
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28 views

Export only one value from a one-band raster

I have a PostGIS database with a georeferenced raster, with one band which contains values from 0 to 255. I should export it to a transparent GeoTiff picture in which the only visible pixels are those ...
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35 views

Determining intersection between list of points and list of linestrings?

I'm coding in php. I have a list of point coordinates (very large one) and a list of linestring geometries (large too). I'd like to determine for each linestring, the point coordinates that ...
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2answers
51 views

Count number of points within certain ranges from a set of points

I have the following, which gives me the number of customers within 10000 meters of any store location: SELECT COUNT(*) as customer_count FROM customer_table c WHERE EXISTS( SELECT 1 FROM ...