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

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What is difference between ST_DWithin and ST_Distance for proximity search in PostGIS?

I have records stored in a table with latitude/longitude coordinates stored in a geometry field. I want to find all records nearby a user supplied reference point. Note "nearby" probably means less ...
8
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1answer
230 views

What spatially-aware GUI administration softwares exist for PostgreSQL/PostGIS (free or paid)?

Most of my experience with PostgreSQL has been PGAdminIII and psql, but I'm interested to know what others use. Is there PostgreSQL equivalent to SQL Server Management Studio (SSMS) and its ability ...
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2answers
187 views

How to query objects within 1000m epsg4326?

I have a postgis table having a column "geom" having a type geometry(MultiPolygon) and the projection epsg:4326 (degree decimal), i want to query all objects within 1000m and i use this query: SELECT ...
2
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2answers
637 views

How to draw bus routes on OpenStreetMap with mapnik

I have successfully set up Postgres with PostGIS and MapNik to serve map tiles. The database is populated with data from OpenStreetMap project. I can see that bus routes are in the data-set, but I ...
0
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1answer
132 views

error in overlapping layers in QGIS

I created two tables with PostGIS, within which I have inserted a shapefile of an Italian region (Apulia) in the first, and the coordinates in the second table. In both tables are set with the ...
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3answers
619 views

How long does it take to load the complete Tiger 2013 dataset into Postgis?

I'm loading the complete TIGER 2013 dataset into a Postgis database and finding that the process is taking an extraordinarily long time. I was surprised by how long it took to load the TIGER 2012 ...
0
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1answer
43 views

How to modify existing geometry type or create new geometry type in PostGIS?

I want to modify PostGIS geometry type TRIANGLE by adding additional information about its neighbours within TIN. WKT representation might look as follows: TRIANGLEN ((0 0 0,1 1 1,1 0 2,0 0 0) ID n1 ...
2
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1answer
2k views

why I can not run hibernate-spatial (in eclipse)

I have a problem with Hibernate Spatial. I followed the tutorial 4.x, and I created my project using maven. after correcting some minor errors in pom.xml and in persistence.xml, executing the project ...
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1answer
125 views

Opengeosuite 4 unable to open psql

When I try and open psql from the postgis menu in opengeosuite 4 on the Mac I get the following error message. “psql” can’t be opened because PostGIS is not allowed to open documents in Terminal. ...
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3answers
4k views

Unable to connect PostgreSQL to ArcMap 10.1

I'm trying to connect my local PostgreSQL database to ArcMap 10.1 but for some reason I'm unable to connect to the server. Any ideas of what might be causing the issue. For the instance option in ...
2
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0answers
81 views

Is there an ArcGIS to PostGIS function cross-reference table?

I was looking back at the presentation called "PostGIS Tips for Power Users" by Paul Ramsey and got to thinking... Has anyone ever seen an ArcGIS Geoprocessing Tool to PostGIS function cross-reference ...
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1answer
139 views

Separating distinct lines in PostGIS

I have a table of linestring segments in Postgis. These segments make up distinct non-intersecting lines as shown by the diagram. To add confusion the direction of the linestrings are not uniform. I ...
3
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1answer
121 views

How to summarize population by neighborhood?

I'm a novice with PostGIS and am currently working on a lab assignment where I have two geometric tables - one containing demographic data by blockgroup (blockgrp2010) while the other identifies ...
0
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1answer
311 views

Install both postgis and postgresql-9.1-postgis packages?

I've installed the PostgreSQL package (ver. 9.1) on a Debian 7 server using the command "apt-get install postgresql postgresql-contrib". I now want to install PostGIS as well. Should I install both ...
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0answers
255 views

pgRouting results to LINESTRING geometry type

I am doing some routing queries, using pgRouting's second version of pgr_trsp function. What I can't do effectively yet is storing the results. That is, I want to able to store in a table: either ...
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2answers
1k views

Converting WKT to WKB

How can I convert a WKT string to a WKB byte[] in Java using postgis functions? I need to save that WKT string in a postgis database (geometry column. Thanks
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3answers
229 views

Is there a way to store time-bounded geometries in PostGIS?

I work with American Community Survey data. ACS is now releasing new demographic data annually, and a new set of TIGER/Line files to go with it. But the vast majority of the geographies (states, ...
0
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1answer
185 views

PostGIS Transform distance or create a view

I have a postgis table that is updated on a regular basis so it is not practical to cast my geometry column to geography So can I modify the following query to convert a distance say 0.5k into ...
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0answers
58 views

SQL questions testing pgRouting 2.0

Following the post:pgRouting 2.0 for Windows quick guide, cuz I have some problem with DB manager(here is the problem I posted:DB manager in QGIS 2.0), I skip DB manager and save the test shapefile, ...
2
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1answer
245 views

DB manager in QGIS 2.0

I followed this post:pgRouting 2.0 for Windows quick guide, and I want to use DB manager to load the test data into my PostgreSQL database. I used url to get the test data: I have set up the ...
5
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1answer
229 views

PostGIS Optimization - Group spatially close entities physically on disk

I'm working on my first PostGIS database and was hoping to find some performance gains for live rendering. I'm rendering a map directly from a PostGIS (9.1, 2.0) db that contains an import of OSM ...
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1answer
104 views

How to restrict buffer extent within land area only?

I need to create buffer for a point feature, but the buffer area will be restricted within the land area only. For example consider the following: A buffer of say 500 km radius is to be generated ...
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1answer
72 views

What is the complexity of neigborhood search in PostGIS?

I have a point with coordinates x and y. I want to know all the points in a square around this point, with side L. For this, in postgresql/PostGIS, I use: SELECT * FROM table_of_points WHERE ...
0
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1answer
205 views

Trouble connecting QGIS 2.0 to remote Ubuntu Postgis

I am trying to connect to a remote postgis 2.0 server (Ubuntu) from QGIS 2.0.1 (installed on winxp). I have been working with QGIS 1.7 / 1.8 on the same database for almost a year without any issue. ...
2
votes
1answer
2k views

Geoserver sql view using an external sql query?

I am trying to figure out a way of producing a view of a layer in GeoServer, using an external sql query. By external I mean, for instance, a user defined query in a php from where all the parameters ...
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3answers
507 views

Create multi-line from point in PostGIS

I'm working on an old table where polygons are stored as points. Now, I want to migrate these points to PostGIS and store them as polygons (or multi-polygons). The table structure is as follows: ...
0
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1answer
649 views

Maximum size on the bounding box with ST_MakeEnvelope and && and geography column in PostGIS?

I've done quite a few google searches, but haven't managed to find anything that has helped me directly. I've got a few features in a PostGIS table with a geography column. The features are focused ...
0
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3answers
152 views

How to extract shape of each segment?

osm2po library does a great job in creating the data required by pgRouting to calculate theshortest paths. But I need the shape (Geometry - LineString 4326) to be extracted when osm2po generates the ...
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3answers
592 views

Table Relate Spatial and Tabular data in QGIS 2.0

I am self taught in GIS, so I apologize ahead of time for my noobness. In ArcGIS you have two options to associate data in a table to spatial data. Based upon my understanding, the first is Join ...
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2answers
1k views

calculating the difference between 2 angles using st_azimuth and dot product

the function below tries to calculate the difference between 2 angles. I use the mathematical reasoning is as follows : 1) Obtain the 2 angles : angle1 = ST_Azimuth(ST_StartPoint(l1), ...
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2answers
1k views

postGIS union multiple tables, big dataset, faster approach?

my goal is simple. I want to union a given set of shapefiles. In the shapefile are stored polygons. The data bounding box is germany, so the data is relatively big. I tried to use all functions ...
2
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1answer
427 views

GeoDjango - return SRID of geometry in GeoQuerySet

I'm wondering if there is a function in GeoDjango which would allow me to determine the SRID of a geometry column in a GeoQuerySet. I know I could do it with a raw SQL query (I'm using PostGIS) but I ...
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1answer
693 views

Can't find libpq when installing PostGIS

I'm trying to install PostGIS 2.2.1 on Mac OS X 10.8. I've installed all of the prerequisites for PostGIS and am now running the configure command: ./configure CC=/usr/bin/clang CXX=/usr/bin/clang++ ...
3
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1answer
986 views

osm2pgsql: Import data in custom projection

I have osm-file and I want to import it to the postgresql via osm2pgsql with custom projection EPSG:20022. I look to the help and found out any keys like -E EPSG: but when I try to do with it I get ...
2
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2answers
187 views

Merging contour lines along tile boundaries

I am working with the CANVEC data set. The data in canvec is broken up in to mapsheets. eg. 116B04. I have data covering the entire province of the Yukon. I have merged all the data in to one ...
2
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1answer
107 views

Stereo Compilation Software with PostGIS

Does anyone know of stereo compilation software that will allow for the writing into a PostGIS database? Both Datum and Stereo Analyst will write to an ESRI Geodatabase. Standard stereo compilation ...
4
votes
1answer
2k views

postgis: difference with && operator and st_intersects

I found that there is a difference in result between using A && B operator or one of the geo functions like st_intersects(A,B) or st_overlaps(A,B) While the st_intersects or st_overlaps ...
2
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0answers
150 views

Using ST_Affine() and trans_param() functions on vector layer

After reading this post How to georeference a vector layer with control points? I decided to give it a try to move/rotation/scale a polygon using Postgis. I have two polygons, polygon_from and ...
4
votes
1answer
505 views

How can I strip out Z values in PostGIS?

How do I get rid of the Z dimension in PostGIS? Specifically, I have some MultiPolygonZs that I want to copy into another table as MultiPolygons. I don't care about the Z values - it's okay to just ...
2
votes
5answers
2k views

How to export raster from PostGIS enabled DB as GTiff with gdal_translate

When I want to export a GTiff from my PostGIS DB with this code: gdal_translate -of GTiff PG":host='localhost' port:'5432' dbname='landslide' user='postgres' password='pass' schema='public' ...
2
votes
2answers
309 views

Separate a polygon in different polygons depending of the distance to another polygon

I have a reference polygon "R", and others polygons (in grey). I want to separate each grey polygon in multiple polygons, depending on the distance to R with different Buffers : - The red line is R ...
1
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1answer
52 views

High number of unique user defined views

We're just at the stage of starting to developing a GIS application accessible through a web front end. We're thinking of using the boundless stack which includes GeoServer and PostGIS. One of our ...
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1answer
322 views

WHERE query when creating layer in MapServer

Is there a way to have WHERE clause when you're querying for postgis data on mapscript ? like, geom FROM country WHERE country = 'usa' USING unique gid. My current workaround is by creating VIEW. ...
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votes
1answer
2k views

Retrive data from database in openlayer GIS

i am using this code but it shows nothing, whats wrong with this code. <!DOCTYPE html> <html lang='en'> <?php $conn_string = "host=localhost dbname=postgis_21 user=postgres ...
11
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2answers
3k views

GUI tools for PostgreSQL/PostGIS?

as a cartographer I work with TileMill to visualize geodata. I installed a local PostgreSQL server with PostGIS and osm2pgsql. Everything works fine. Anyhow, I am new to working with servers and the ...
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1answer
3k views

Postgresql Trigger to insert records in my table from another one

I spent few days trying to resolve this question but it was impossible. I have two tables: Table1. CREATE TABLE point ( id_point integer NOT NULL DEFAULT, layer text, elevation numeric, ...
4
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0answers
501 views

Hibernate Spatial - 'Invalid endian flag value encountered' Exception

I'm trying to run a simple query in Hibernate Spatial 4.0 on PostgreSQL 9.3. I have a number of objects in a table with latitude/longitude values, and I'm trying to query objects that fall within a ...
2
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3answers
306 views

How should I implement a many-to-many relationship in a web mapping application?

Scenario: I am given a layer of point locations called "problems." These will be displayed on a web map. Users will then use the web map interface to create and populate field information for a point ...
0
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1answer
711 views

Unable to load PostGIS vector layer into QGIS using python cookbook recipe

I'm having trouble loading a PostGIS layer using Dufour (from osgeo4w), using the guide at http://www.qgis.org/en/docs/pyqgis_developer_cookbook/loadlayer.html. I just get the 'invalid layer' message. ...
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1answer
825 views

Postgis functionalities in Microsoft SQL Server

I'm using Postgresql 8.4, Postgis 1.5 for My GIS works. Planning to change my Database to Microsoft SQL Server 2012. Can we use all the Postgis functionalities in Microsoft SQL Server 2012. Please ...