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

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588 views

How to save a newly created shapefile in PostGIS?

I am creating shapefile using shapefile.py and my database has records more that 65k which is the limit of the shapefile. How can I create shapefiles then? Is it possible that somehow I am able to ...
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1answer
2k views

How to filter features in a layer?

I am trying to display certain features in a shapefile-based layer using QGIS. I have found the subset function in the properties panel, which does exactly what i want, but is too tedious given that I ...
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1answer
1k views

How to get the coordinate system from a PostGIS database?

My question is probably amazinlgy stupid, but I can't find the answer myself. I would like to extract from a database the latitude and longitude of points. For now, I'm getting x(the_geom) and ...
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1answer
57 views

When would a PostGIS geometry compare using ~= return true when ST_Equals returns false?

I have a couple of featureclasses in a 10.2 geodatabase/PostgreSQL 9.2.2 database and I've been struggling with the FeatureCompare tool--it is telling me geometries are different on some features ...
2
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1answer
48 views

PostGIS: How to understand ST_RasterToWorldCoord() right? (PostGIS 2.0)

After putting raster in to postGIS by this Thank @Sorin for helping me out! Now, I want to output raster tile, then view it on QGIS. But the problem is the output of ST_RasterToWorldCoord(raster ...
2
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1answer
64 views

How to change table name of command raster2pgsql

I am completely newbie with GIS and PostGIS as well I'm trying to load raster into postgreSQL with raster2pgsql. It runs well. However, the table name of the raster is generated automatically. For ...
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1answer
93 views

How can I move along a line (or path)?

Given a line (street, railroad, river...) I want to simulate a moviment inside this line. Example: See this picture: Say I'm in "Nagqu" and want to move to "Kunlunqial". In a time (t=0) I'm in ...
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1answer
409 views

GeoTools and PostGIS with ESPG:3857

I'm trying to use both PostGIS and GeoTools with the same ESPG:3857 projection, however, it looks like the projections in PostGIS and GeoTools differ. This is what I have in PostGIS: PROJCS["WGS 84 ...
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1answer
509 views

PostGIS Dissolve/Union close polygons

I have approximately 1 million polygons that have been split by lines. However, this has caused one half of a polygon to be separated by approximately 50cm from its other half. After doing a lot of ...
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1answer
182 views

How to merge connected lines with same direction (PostGis)

I am looking for a way to join all lines that are connected, have the same direction, i.e. start point of one is end point of the other, and share some common attributes. In fact, I want to connect ...
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2answers
223 views

Can Geoserver return the raster value of a lat/lon point

I have a GeoTIFF published by Geoserver 2.2 and being used by Leaflet via WMS. How can I get Geoserver to return the raster value at a lat/long point? I'm guessing it has to do with using WCS, but ...
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1answer
245 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 ...
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2answers
896 views

KML from EPSG:4326 to EPSG:900913

im trying to create KML files manually (XML format) by extracting data from a postGIS database with "geography" values in a column. But i belive i need to transform the projection of each row in the ...
2
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1answer
692 views

How can I fix QGIS PostGIS Manager error 'shp2pgsql' is not recognized?

I have QGIS 1.8.0 installed via OSGeo Installer and work on win 7. All I need is to upload the shapefile to the database via this plugin. Unfortunately I am receiving an error: Something's wrong: ...
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0answers
199 views

From pgRouting shortest_path back to osm node id

I'm successfully performing path finding queries like shortest_path on data imported with osm2pgrouting. The tables I have inside my pgrouting DB are the following: List of relations ...
2
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1answer
313 views

Querying PostGIS Raster with MultiPoint

For one of my projects using PostGIS 2 I have a table with GPS tracks (igc_files). It holds records including a MULTIPOINT() column that has about 1,000 points for each record and a column that has an ...
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1answer
638 views

How to find polygons inside polygon with PostGIS 2.0

I have a relation representing all the counties in my country and the other one containing all the districts - e. g. each and every county is composed of several districts. How do I select them with ...
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3answers
778 views

How to speed up Postgis raster layer display in QGIS?

i've been importing some digital orthophoto geotif files into postgis 2.0.1 via raster2pgsql tool (i also made 3 levels of an overview table - pyramid). Then i tried to import the layer into qgis via ...
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3answers
702 views

adding non spatial attributes using geoserver

I am using Openlayers + geoext to perform transaction operations in postgis database using geoserver . i can insert spatial data into postgis but cannot insert other data like road name, road type in ...
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1answer
372 views

accessing postgis raster data using Query layer in ArcGIS

I tried to load raster file (jpg) into post gis using the syntax provided here "C:\Program Files (x86)\PostgreSQL\9.1\bin>raster2pgsql -I -C -e -Y -F -s 102003 -t 300x300 ras_test.tif ras_test1 | psql ...
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0answers
328 views

PostGIS: ST_Transform function conversion problem

I'm inserting map data from a GML file with srid EPSG:27700 into a PostGIS database table with srid EPSG:4326. I'm using the ST_Transform function as in this snippet: ...
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2answers
767 views

Select Duplicate Points PostGIS

I have a table made of merged point datasets in PostGIS. I want to select all of the features where two or more points have identical geom values. At present I just want to select so I can review ...
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2answers
2k views

Problem when calculating longitude and latitude for points

I have a PostGIS database with SRID=900913 (Google Mercator) and I would like to know the latitude and longitude of points. I use this command: ST_X(ST_TRANSFORM(the_geom,4283)) Following what is ...
2
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1answer
365 views

The minimum bounding circle of geometry that crosses the 180th meridian

Background: I've been given a task where I have to calculate the minimum bounding circle of Alaska (for the purpose of running a Roeck test). I'm using the Census' state level geometries available ...
2
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1answer
2k views

Basic MapServer query of PostgreSQL/PostGIS database

I've just installed MapServer on a linux server and I am trying to understand how to display a basic map using a PostGIS database. I have displayed a shapefile in the browser, so I know that the ...
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2answers
298 views

unable to call shp2pgsql using python

I am unable to call shp2pgsql using python as I have to pass various options like (-s -a -i) and I am not getting the required output .. Method I am using is p1 = subprocess.Popen(["cmd", "/C", ...
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1answer
697 views

GeoServer converting PostGIS timestamp with time zone

In a PostGIS view i have a field of data type "timestamp with time zone". In GeoServer this field is show with datatype "Timestamp" My problem is that i want the Timestamp to be show in my ...
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5answers
4k views

Error importing Shapefile to PostGIS using Importer GUI

I'm trying to import a shapefile into a PostGIS database using the graphical importer. I just installed POSTGRESQL, and PostGIS. The GUI looks like this: After testing that my database worked, I ...
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0answers
41 views

Display postGis query result on Google maps Api [closed]

I have MULTILINESTRING Geometry in Postgis and as Google Api does not provide any way to plot MULTILINESTRING , i'm converting MUltiLINEstring to LINESTRING through ST_Merge function. But when i'm ...
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1answer
49 views

PostGIS convert GeoJSON to geography

While there are functions to convert geography to GeoJSON: text ST_AsGeoJSON(geography geog, integer maxdecimaldigits=15, integer options=0); I do not see any way to go the opposite direction ...
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64 views

How to create a regular polygon grid in Openlayers?

I am trying to create a grid in my map and do some calculations. I seen the following links:- Create regular polygon grid using postgis Create regular polygon grid inside a polygon using postgis ...
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1answer
193 views

How to Import ESRI Geodatabase format .gdb into PostGIS

I ran into a problem when loading a ESRI Geodatabase format .gdb into PostGIS. I have data 2.5GB GDB file. I followed some tutorials on the internet, but it seems that doesn't work out. I created a ...
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1answer
1k views

Installing postgis on postgresql 9.1 not working

I'm trying to install Postgis 2.0 on a perfectly functionig postgresql 9.1.10 database. I installed the package via: richard@srv1:/$ sudo apt-get install postgresql-9.1-postgis postgis Reading ...
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0answers
32 views

How to load or query data directly to R from a PostGIS database using RPostgreSQL and rgdal [duplicate]

Is it possible to load/query a shapefile to R, which is stored in a postgres/postgis database? I've built up a connection to my postgres database via DBI, RPostgreSQL and I want to make some ...
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2answers
286 views

ST_DWithin uses Geometry or Geography type

assuming I use the following query to match the locations to a poi within 10km distance: SELECT poi.poi_id, h.loc_id, (ST_Distance(poi.geom,h.geom)*111.111) as distanceinkm FROM iut_poi_transl AS ...
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1answer
429 views

How to split line layer at polygons' boundary of a polygon layer?

I have a line layer and a polygon layer in PostgreSQL 9.2, PostGIS 2.0. How can I split every line each time it crosses a polygon's boundary?
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1answer
693 views

How to create shortest route and multiple routes service using openlayers?

I created a digital database of many important features and locations of my city. and I want to create a web application in which shortest distance between two locations can be calculated and ...
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1answer
307 views

Problem connecting to localhost PostGIS

When I try to connect to a small localhost PostGIS database using QGIS, I get the error message: FATAL: no pg_hba.conf for host "fe80::4528:3236:418a9e7b%10" user "postgres", database "nyc", SSL off ...
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2answers
169 views

How to remove shapefile from PostGIS

I added a shapefile to the PostGIS using, ogr2ogr -f PostgreSQL PG:"host=server_ip user=username dbname=dbname password=password" yourshapefile.shp; Now I want to remove it. What is the command ...
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2answers
1k views

How to offset point perpendicular to line direction in PostGIS

I have a postgis table of points, that are sitting on road centerlines (I've linear referenced them). And the second table with road centerlines themselves. The point table also has a field roadid and ...
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3answers
372 views

Java shared hosting with PostGIS

I've been developing a disaster risk management application that makes use of Java/Smart GWT, PostgreSQL/PostGIS, and Tomcat 7. I'm looking for a shared hosting environment for the beta testing period ...
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0answers
975 views

how can we save vector files in openlayers

i'm using Postgis + tomcat + geoserver + openlayers for my application. with the help of some tutorial i have reached upto gettting feature information of layers. Next i want to edit and save ...
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1answer
94 views

Which SRS is computational more effective to store continental scale data? (given some conditions)

For a Precision Agriculture application I need to make calculations in UTM projection. The data will be stored in Postgis and is made of soil samples results (point data) and field boundaries of many ...
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1answer
813 views

Mapserver/PostGIS Query Error

I'm having some difficulty understanding the error I am getting from my mapserver/postgis program. I have the following map file: MAP # start of map file NAME "sample" EXTENT ...
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1answer
2k views

Problem inserting Geometry into PostGIS Table

I am new to Postgis and I have imported a shapefile containing point layer into the postgis, and the SRID i had chosen was 4326. now while inserting the values into the table I am getting problem. My ...
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4answers
734 views

Failing to build PostGIS on OS X 10.7 Lion

I am trying to install postGIS from source to match the default install of postgreSQL on OS X 10.7. I installed GEOS and PORJ.4 from Kyngchaos and ran $export MACOSX_DEPLOYMENT_TARGET=10.7 $export ...
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1answer
128 views

Get relative north aligned point 2163 (US Equal Area)

What I'm trying to do is create a grid where the y axis is north aligned. I have a origin Lat/Lon point which is the bottom left corner of the grid and each cell should be 100 by 100 meters. So I ...
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2answers
588 views

PostGIS - certain MultiPolygons cause “BOOM! Could not generate outside point!”

I've just posted this at StackOverflow and someone suggested I try here. Original: http://stackoverflow.com/q/5863859/246265 I'm trying to represent a rectangular area which crosses 180 degrees ...
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1answer
515 views

Circle features missing in PostGIS after import from ArcGIS using ogr2ogr

I have a ArcGIS feature class of geometry type polygon. It was created as a convex hull with a 200 meter buffer on a point dataset, aggregating rows on a particular field. The number of points used to ...
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2answers
100 views

Unable to implement pgrouting(plugin) pgr_astar routing algorithm (shortest path) [duplicate]

I have been working on a project for indoor navigation. I made the floorplan of the building and road-map for routing purposes as shp files (using JOSM, making GeoJSON and then converting to shp file ...