PostGIS is an extension for the PostgreSQL object-relational database that adds support for geographic objects.
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How do I get started with PostGis
I have been reading a lot about it, but I am struggling to find a good beginner's guide.
Which tutorials/books do you recommend? My past experience involves python and arcgis. But I have never worked ...
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How to create Vector Polygons at the same amazing speeds GISCloud is able to render them?
EDIT (outlining new bounty added):
I have added the largest bounty possible to this question in hope of getting a very detailed answer. Your solution should outline a step-by-step guide utilizing open ...
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Best practices for PostGIS production environments?
What PostGIS documentation have you come across that has been helpful when tuning PostGIS for a production environment?
I would like to get together with my DBA to setup a Postgresql/PostGIS ...
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Spatial clustering with PostGIS
I'm looking for spatial clustering algorithm for using it within PostGIS-enabled database for point features. I'm going to write plpgsql function that takes distance between points within the same ...
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What coordinate system should be used to store geography data for celestial coordinates?
I am doing an astronomy project. I want to have the information about our images stored in a spatially enabled database. This, I would think, should be a very easy special case for GIS functions ...
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ArcGIS and PostGIS
Has anyone successfully used PostgreSQL with PostGIS successfully? I am a semi-experienced ArcGIS user and want to build out a database and connect it to ArcCatalog. I've scoured the internet for ...
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PostGIS: What are the pros and cons of geography and geometry types
My company uses geometry (the_geom) data type for storing geospatial data.
I've recently been acquainted to the concept of geography (the_geog) data type which, as I understand it, stores the SRID ...
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How can I connect to a PostGIS database from ArcMap 9.3 and 10.0?
How can I connect to a PostGIS database from ArcMap 9.3 or 10.0?
Ideally, I would like to be able to perform spatially enabled queries and receive the results back (e.g. spatial and non-spatial ...
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Options for displaying PostGIS vectors in OpenLayers
I am very new to web-mapping, so this question may be a little misguided.
I want to have a very simple web interface using OpenLayers (or even Google Maps if that will be easier) which can display a ...
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Curved point-to-point “route maps”
I have recently been looking at airlines web pages that display their routes departing a certain city to all other cities they service. I would like to be able to create similar curved routes between ...
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Optimizing osm2pgsql imports for OSM data
I'm currently building an instance on EC2 on which to import the entire Planet.osm snapshot of the whole Earth's worth of data for some projects we're working on. I've spun up a large Ubuntu x64 ...
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Would PostGIS offer an advantage over MySQL for a produce farm application?
I have a web app that stores the locations of farms in West Michigan. You can search for a product (e.g. "broccoli") and it will show you all the farms that grow that product.
Right now I'm using ...
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Spatial databases learning resources for newbies
Would be taking up a course on spatial databases next semester. Would anybody know a newbie friendly introductory resource? A vendor neutral one would be preferable. Thanks.
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When should you NOT use a spatial index?
I am asking this because I was mainly working with Oracle but for the past year I've been doubling with PostGIS and SQLServer 2008. Most spatial functions in Oracle won't work without a spatial index ...
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2answers
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How to create a regular polygon grid in PostGIS?
How to create, on the shape of a polygon, a regular grid of polygons/squares of an given size, in postgis?
I have thought about a function like Create regular point grid in Postgis only for squares, ...
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Alternatives to pgRouting
I was wondering if there are any alternatives to pgRouting tools.
Thinking about it for a bit, I think the only alternative is to use R or RPY to do the analysis.
Basically I'm trying to solve ...
17
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2answers
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Acquiring ArcGIS-like speed in Postgis
I have been using Postgis 2.0 for 3/4 of a year now and while I really enjoy using it, excessive query processing time has rendered it basically unusable for my use case.
I tend to do heavy ...
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How to migrate GDB data into PostGIS without ESRI apps?
Can you tell me how I can load geodatabase data into PostGIS without having to install ESRI apps? The solution I found online talked about using ArcGIS to convert GDB to SHP and then importing SHP to ...
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How can I calculate the average width of a polygon?
I'm interested in examining the average width of a polygon that represents the road surface. I also have the road centerline as a vector (which is sometimes not exactly in the center). In this example ...
16
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2answers
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Best GIS system for high performance web application - PostGIS vs MongoDB
I am working on a web/mobile application based on location data. Since i am already familiar with MongoDB, i found the geospatial indexing of mongo is quite suitable for my needs. As i am mainly ...
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4answers
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How to create regular point grid inside a polygon in Postgis?
How to create, inside a polygon, a regular grid of point spaced x,y in postgis? Like the example:
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4answers
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Separate polygons based on intersection using PostGIS
I have a PostGIS table of polygons where some intersect with one another. This is what I'm trying to do:
For a given polygon selected by id, give me all of the polygons that intersect. Basically, ...
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Generalisation Strategies for Building Outlines
I have a dataset of building footprints vectorised from a raster dataset. The dataset is currently just a vector representation of the raster data. I would like a polygon dataset that only has ...
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What's the status of Postgis 2.0 topology support in QGIS?
Having followed the Postgis developments over the past 6 months I have noticed a bunch of features which seem to be incredibly cool especially in the area of topologies and associating calculations on ...
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Comparison of geocoding solutions (such as Gisgraphy & PostGIS 2.0)
As I am sure many of you are aware, PostGIS has finally released Version 2.0 and included within this version they have also built a geocoder (see: http://postgis.refractions.net/docs/Extras.html).
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Bulk load multiple shapefiles into PostGIS
I've got over a hundred data layers in shapefile format that I want to upload into a PostGIS database. They are all in the same projection, but represent different data layers so they do not have the ...
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How do you best deal with data that spreads across UTM Zones?
I have data that spreads across two UTM Zones GDA/MGA94 UTM Zone 55 and 56. I have layers such as a cadastre, roads, pipelines etc where I want to store measurements like lengths and areas in metres ...
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How to make a spatial view in PostGIS and add it as a layer in QGIS?
In PostGIS 2.0, what is the most efficient way to create a spatially enabled view that is viewable in QGIS?
I followed the context of Part 2 of @Mike Toews answer to this question, and the view ...
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What are some high-profile websites that use OpenLayers and PostGIS?
I think there are many convincing arguments for using PostGIS but I am interested in showing people examples of websites that use PostGIS and OpenLayers.
Some examples that I have seen are:
...
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4answers
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How to create a simple front-end for a PostGIS database?
My organisation collects a lot of environmental monitoring data (stream flow, water chemistry etc.) most of which is currently stored in Excel. I’d like to get everything into a database – probably ...
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6answers
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How do I get started with GIS Servers on Amazon EC2?
Are there any tutorials, talks or presentations that discuss the use of EC2 or other cloud computing services to host GIS Servers? Has anyone had any experience in doing it with Amazon's EC2? How hard ...
14
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2answers
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Moving a PostGIS Installation
I have a simple question:
I have a postGIS installation running on an old computer that I'd like to move. I spent a bunch of time playing with pg_dump and pg_dumpall without success. It seems the ...
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How can I find a point inside a polygon in PostGIS?
How can I find a point that is guaranteed to be within a given polygon in PostGIS?
I am aware of the ST_Centroid function. However, the centroid is not always within a polygon, see below:
...
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2answers
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What are hardware requirements for a cloud hosted PostGIS & GeoServer?
I have been playing with a local installation of PostGIS & GeoServer. I would like to move my work online now to share it with several collaborators.
The proof of the concept map will consist of ...
13
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5answers
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What in-depth spatial database systems tutorials exist?
Is there a good tutorial that explains in depth the internals of a GIS and a spatial database system such as PostGIS with examples and without any background assumption? I'm specifically looking for ...
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Shapefile PRJ to PostGIS SRID lookup table?
I was wondering if there is such a thing as an shapefile PRJ to PostGIS SRID lookup table? Something that can translate the most standard shapefile PRJ definitions into the likely SRID.
When using ...
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Nearest neighbor between a point layer and a line layer
I've asked this question several times on stackoverflow and irc between #qgis and #postgis and I also tried to code it or implement it my self in postgis with no real answer.
Using programming (most ...
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How can I calculate the bearing between two points in PostGIS?
How can I find the bearing between two points in PostGIS?
Please specify in your answer whether or not the method producing a bearing on the spheroid, or a planar bearing.
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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 ...
13
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1answer
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Identifying topological relationships using PostGIS
I'm trying to perform a basic typology analysis using PostGIS. My objective is to find any polygons that touch other polygons. To do this, I thought the ST_GetFaceEdges would work
(reference). I want ...
13
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2answers
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Identifying road intersections using PostGIS
I'm trying to identify where roads intersect each other, and to make a point at this intersection, with the number of roads that form the intersection listed.
I was wondering if there was some way ...
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3answers
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In PostGIS is it possible to create a View with a unique ID?
When I create a view in PostGIS is there any way to add a unique ID to that view? Just like the "gid" field in any other PostGIS table?
Edit: Sorry I should have included this in the original post. I ...
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3answers
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Visualization of 3D shapefiles with Mapserver and Postgis
I'm wondering is there a way to visualize 3d data with mapserver? 3D .shp files are in postgis database, and I already connected mapserver to database, but with simple layer in mapfile.
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How can I merge/collapse nearby and parallel road lines (eg. a dual-carriageway) into one single line?
I have a shapefile from OSM which contains all the roads within a city. Larger roads (like dual-carriageways) seem to have 2 parallel lines. I'd like to collapse / combine those into 1 line so I can ...
12
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4answers
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The best language to program with GDAL
I'm going to start to create programs to handle geographical data from a PostGIS server, and going to use GDAL.
According to your experience, with the best language to program with it? I can program ...
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How to batch synchronize data from ArcSDE to PostGIS?
Its been suggested that i ask this question again, but perhaps worded differently than how to Bulk load multiple shapefiles into PostGIS.
I'm new to postgis and sql but i want to use postgis as a ...
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4answers
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Database design: road topology in GIS
Is there a standard or a best practice way to store certain features about roads:
Road directionality:
One way streets: Roads going in one direction only
Center Turning lanes: roads that exist ...
12
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3answers
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Centralizing shapefile data into database
I've got hundreds of shapefiles from various different GIS projects that I want to start consolidating into a single database platform, currently attempting this with Postgres / PostGIS.
Hardly any ...
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4answers
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What is a suitable Global/Universal Unique Identifier for a PostGIS database?
I have read that using OIDs as a primary key in a postgreSQL/PostGIS db is poor practice because there are instances where these can be reset. Sounds logical, but then what is a suitable alternative? ...
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How to create one-sided buffers or parallel lines in PostGIS?
I'm looking for a way to create so-called one-sided buffers or parallel lines in PostGIS. Example: 1. buffer, 2. one-side, 3. both-sides
I've found some discussion on the mailing list from 2009 and ...
