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

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3
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1answer
654 views

remove duplicate points based on a specified distance

i have a table of points with each point acquired on a specified date, by a specified source, and having a measured value. i want to consider points as duplicates if they have the same date and if ...
0
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1answer
255 views

How to remove polygon under other one?

Hi, lets say that green polygon is under red and part of blue with yellow stripes is also under red polygon. how can i make one polygon from every polygons that intersects my main ( red ) polygon ...
0
votes
1answer
985 views

Adding MySQL to Geoserver for Non-Spatial Data

I need to connect to a MySql table, which has all the attribute values and the lat & long. I am using a GeoServer Suite to host my raster and so felt the best way to go about it would be to add ...
-1
votes
0answers
44 views

Determine the Closest road to a GPS point [duplicate]

Possible Duplicate: Calculate distance of point from an arc/polyline I have been trying to find the road to which a GPS point is closest to. I have a postGIS database which i loaded with ...
6
votes
1answer
2k views

Postgis - Converting 'geometry_dump' data type to a 'geometry' type

I am working with a dataset of property boundaries that has had ST_Union() run on it, thus all the polygons appear as a multi polygon in one row of a table. I would like to separate these out so I get ...
3
votes
2answers
687 views

Merging polygons that intersect by more than a specified amount

I am working with a dataset that contains a subset of property boundaries in a local government area, thus my dataset is made up of several thousand properties but not all are touching. Since it is a ...
6
votes
1answer
159 views

PostGIS ERROR: BOOM! Could not generate outside point!

This may be a continuation of a closed thread. I want to sum the areas of polygons over categories in a large data set (avian species ranges), like this: select sciname, ...
4
votes
4answers
2k views

Calculate distance of point from an arc/polyline

Using Postgres/PostGIS, I am trying to query the database for the closest arc to a particular GPS point. Each Arc is made up of two nodes that are GPS points on a map. Is there a way I could query ...
3
votes
1answer
193 views

How to query latitudinal bounds on 95% of a polygon in PostGIS?

I'm going to say thanks in advance. I'm very new to GIS and this forum is a tremendous help. My simple questions have been solved; here's one that might be a little trickier. Given a polygon in a ...
19
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2answers
5k views

Looking for fastest solution for Point in Polygon analysis of 200 million points

Apologies for asking a question that has been asked before -- I've read through answers, and I'm left wondering how to implement the recommendations. I've never used SQL, Python, C, and have only ...
0
votes
2answers
1k views

How to insert a point into postgis from php?

For the following line, I received an error in my php page, but the query is OK when I run it from pgmyadmin. I am trying to insert a point into my postgis from php which contains name, address and ...
3
votes
2answers
1k views

How to query aggregate max, min, median latitude of polygons in PostGIS?

I am just starting to learn how to use PostGIS (1.5.4) and my SQL skills are essentially those of a competent beginner. Having perused the PostGIS documentation and searched these forums, I'm not ...
4
votes
4answers
1k views

OSM To Postgis & WGS84 problems

I’m trying to import OpenStreetMap (OSM) data into postGIS it doesn’t appear to be working in that features do not appear to be in the correct place.. Using the QGIS OSM add in and a coastal shape ...
1
vote
1answer
3k views

Google Maps MarkerClusterer - Remove all clusters

So, I have a PostGreSQL DB with 317 datapoints - all spatially enabled through PostGIS. I have queried this using PHP as GeoJSON and overlaid it on Google Maps (using a converting routine). I have ...
13
votes
2answers
21k views

How to insert a point into postgis?

I have created one table in my Postgis. But I can not insert point. I do not know what's wrong with my query? CREATE TABLE app ( p_id INTEGER PRIMARY KEY ); SELECT ...
4
votes
2answers
312 views

Fastest way to remove matched points

Hoping someone can see a faster way of doing this, because at the moment I'm averaging 9 hours per run for what I'm trying to do and well basically getting my behind chewed off by the boss :-) The ...
2
votes
2answers
546 views

How to create hibernate layers at runtime?

We need to dynamically create hibernate layers from shapefiles. As far as we understand, the workflow is following: Import shapefile to database(creating new table for each shapefile?) Is it good ...
4
votes
2answers
5k views

Struggling with enabling a PostGIS database on Mac

I have installed PostGIS on the mac using the binaries available on http://www.kyngchaos.com/software:postgres Postgres v 9.1.3 PostGIS v 2.0 After that I want to enable postgis for my database. I ...
6
votes
3answers
1k views

Large Open Street Map OSM file to Shapefile. Is there any hope for 32-bit FME?

I have a large OSM XML file (around 8 GB) that I was hoping to process in FME. I have a workbench that I previously used to process smaller files (500 MB) into feature type-specific Shapefiles (e.g. ...
2
votes
1answer
3k views

KML PHP parser to INSERT into database

So I have a KML file which has attribute data(Inside the tag with about 12 data points). This file was generated on ArcGIS. I'm trying to write a PHP script to parse this KML file and insert the ...
1
vote
0answers
45 views

How to load GeoJSON files directly onto QGIS? [duplicate]

Possible Duplicate: Plugin or script to get QGIS to display geoJSON in a layer Is there a way to do this? Or is there a way i can put it onto PostGIS and then load it onto QGIS? I actually ...
4
votes
1answer
1k views

PostGIS geometry intersection test results different for Point and Linestring

Can anyone please tell me what I'm doing wrong, and how do I avoid the problem? I'll attempt to clarify what I'm doing as things go along. The geom column is a multipolygon column, all values are ...
2
votes
2answers
902 views

DatabaseError: Coordinate values are out of range [-180 -90, 180 90] for GEOGRAHY type

I am using Django 1.3, PostGIS 2.0 , Postgresql 9.0 and GeoDjango. I had a database with a table for places. This table had latitude and longitude for places in the US. I enabled this database with ...
6
votes
1answer
566 views

Data visualization and maintenance tool

Background Looking to leverage an existing GIS system for exploring organizational data. Architecture The following figure represents a high-level overview of the system's desired features: The ...
10
votes
6answers
2k views

Should I use a CMS for my web mapping application?

For my web mapping app, I am using GeoServer as server, PostGIS as spatial DB and OpenLayers on client side (as well as other JS libraries). The map is composed of base maps and vector layers. One of ...
6
votes
1answer
493 views

Filling a polygon with lines using Postgis

i need to calculate a specific distance in an area. The distance is calculated from parallel lines in a polygon, And i need to find out how many parallel lines (with x meters distance to each other) ...
1
vote
1answer
131 views

Generate source_id and target_ id for every segment in a multilinestring geometry (PostGIS|PgRouting)

I am working on a project that requires finding the shortest path and to achieve this, I've used the PgRouting dijkstra function and it's all worked out perfectly. Initially, the road network was ...
0
votes
0answers
21 views

Unable to create spatial database for geodjango [duplicate]

Possible Duplicate: How to verify a PostGIS installation on OS X? I am trying to install PostGIS for MacOS X and uptil now this is what i got PostGIS is now configured for ...
3
votes
1answer
379 views

How to connect PostgreSQL from osm2pgrouting

I am using OSGeo Live. It is an Ubuntu system. I installed it in my PC. I was following one pgRouting workshop. http://workshop.pgrouting.org/index.html In one step, I needed to connect ...
1
vote
1answer
321 views

Identify functionality using mapserver

I am just creating a simple web application using mapserver. It has the basic pan, zoom in/out functionality. Now what I want to try is to get an identify functional added into it so that when I click ...
7
votes
4answers
886 views

Output PostGIS geometry data as centroid or polygon depending on zoom level (GeoServer)

This is what I want: when I zoom out, cities of the country should appear as points and at a certain level when I zoom in, I want them to appear as polygons (showing the area of the city and ...
3
votes
2answers
646 views

OSM To Postgis & WGS84 Newbie confusion

Hi I wonder if someone can clarify as I'm confused. I need to load planet OSM data into Postgis so I downloaded a small data set of a UK County and followed the instructions here loading the Google ...
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0answers
79 views

Install PostGIS from beginning [duplicate]

Possible Duplicate: How to verify a PostGIS installation on OS X? Ok, so i tried installing PostGIS for MacOS X from HomeBrew. Once i started installing, brew install postgis It ...
1
vote
1answer
1k views

How to verify a PostGIS installation on OS X?

I am trying to set up GeoDjango and installing PostGIS on my mac and when I am trying to ./configure I am getting this error checking PostgreSQL version... PostgreSQL 8.4.9 checking libpq-fe.h ...
1
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0answers
94 views

How to maintain schema when copying feature from layer 1 to layer 2, where both layers have same schema?

If I load two unique layers, wherein each layer contains unique data, but both layers share the exact same schema, why is it when I copy a feature from layer 1, and paste it into layer 2, the ...
5
votes
1answer
518 views

Speed up pgRouting point_to_id using new <-> operator in PostGIS 2.0.0

The point_to_id function, which assigns a node id to a point based on existing nodes and tolerance, is using a query as follows: SELECT id, the_geom FROM vertices_tmp WHERE ...
1
vote
1answer
98 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 ...
4
votes
3answers
2k views

Geometry issues when creating table from existing spatial table

In short, I want to split an existing spatial table into two parts. The split itself is straight forward. I start with this (fully functioning) table: CREATE TABLE table ( my_identifier smallint, ...
3
votes
4answers
2k views

How to ceate a point layer from a table in PostGIS?

I have a table in PostgreSQL(postgis). This table has latitude and longitude values in it. Now I want to plot these point in qgis. The only thing I could get done was connecting to the database from ...
3
votes
2answers
2k views

How do I get the distance meter value between two geometries in PostGIS?

I have a simple question about calculating distances in PostGIS. I would like to get the distance between two geometries. I am using this sid : 4269 in meters what i am doing now is this : ...
4
votes
1answer
343 views

Find the farthest point (PostGIS)

I have a table with 2000 records and with those columns OutletName, longitude, latitude, geom I would like to find a way to find the farthest outlet between a selection of outlets For example we ...
7
votes
1answer
2k views

Output polygon data from postGIS and read it on Google Maps API

So, I have a group of polygons stored in PostGIS. I'm trying to build a web application with Google Base maps (using Google Maps API). Now, How do i output the polygons in the right format so that ...
5
votes
2answers
810 views

Loading data onto PostGIS using KML files with attibute data

So, I have a kml file which contains 317 data points (317 polygons and the respective 317 names). The kml file also contains attribute data which pops up in a bubble on Google earth with about 12 ...
3
votes
1answer
885 views

Convert KML to shapefile without losing attribute data

So I want to convert KML files to SHP shapefiles to load it onto PostGIS. Currently I'm using ogr2ogr to do the conversion for me, but it wipes out all the attribute data. How do i preserve this ...
5
votes
1answer
805 views

SQL Query to Reverse Geocoding in PostGIS

I try to do Reverse Geocode from my shapefile on the database. I'd already try with Spatialite and PostGIS to put shapefile (.shp) into it. But I'm still can't delivered my objection about reverse ...
5
votes
2answers
937 views

How are housenumbers and streets linked in a OSM based PostGIS DB?

I'm trying to understand how OSM is linking housenumbers and streets with each other. I downloaded an osm file for germany and imported it into a PostGIS DB. To understand how the linking is working I ...
1
vote
1answer
363 views

How to cast box3d_extent to geometry (Rare problem with Geoserver and Postgis)

I use Geoserver 2.1.3 and "POSTGIS="1.5.3" GEOS="3.2.2-CAPI-1.6.2" PROJ="Rel. 4.7.1, 23 September 2009" LIBXML="2.7.6" USE_STATS" on PostgreSQL 9.1 From time to time (well - today I can't get around ...
3
votes
1answer
2k views

How to find the nearest point projected on the road network?

I would like to know if there is a function at pgRouting that given a point (lon/lat) can give you the projection of that point to the road network . Thanks in advance john
2
votes
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 ...
3
votes
1answer
2k 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 ...