Digital Geography

Colaborative Working in PostGIS

The last days I needed to work with other geoenthusiasts on a PostGIS database. Unfortunately, as you upload a layer from QGIS you will be the owner of the new created table and no one is able to alter it by default. Here I show you, how to change this using some “trigger functions” and some shared roles.

Short Note: export layers to PostGIS with Processing

When using QGIS along with PostGIS you might want to publish data directly from inside QGIS into your PostGIS database. This is not only convenient as you don’t need to change the software of use but also easier as it only takes a drag and drop in QGIS instead of any commandline/fancytool. Yet it comes with a disadvantage: the number of inserts from QGIS into the db is limited to 200 per transaction. So it will take some time to insert a bigger dataset with 150.000 points or so. So how to overcome this?

PostgreSQL and PostGIS: A brief introduction

You probably seen this already (maybe on your very own PC as well): A folder with shape files. Well we’re living in the 21st century and I do have and use those folders still. After a talk of Sebastian Meier at Maptime Berlin I was convinced and started to work with a databases instead of folders. So let me show you how to install PostgreSQL along with PostGIS on Ubuntu and Windows, how to get data into it, import OSM data and how to connect it with QGIS/ArcGIS.

Import OSM Data Into A PostGIS Database (The Easy Way)

I often find myself in a situation where I want to work with large areas and datasets of OpenStreetMap data. No matter if you want to use them in a QGIS map or create custom map tiles in Tilemill, with the Overpass API you quickly run into performance issues. Imposm is a great tool to overcome that situation, so you can load OSM extracts (worldfiles in pbf format) with a custom data mapping into a PostGIS enabled PostgreSQL database. The downside: It is hard to set up if you are not a database and system admin guru. This is where…

HeidiSQL vs. pgAdmin III – a small speed-test

HeidiSQL, a free database-client, now supports PostgreSQL/PostGIS in the newest nightly builds. Using HeidiSQL with MySQL was always a pleasure and I often had the feeling that the pgAdmin III client of PostgreSQL is slow and not very user-friendly in some points. Because of this I had to test the difference of performance of these two clients. I don’t want to talk about features and handling because this is on the one hand a matter of taste and on the other hand the support of PostgreSQL is very new in HeidiSQL. Instead, I want to compare some simple SQL-queries in…

OpenSource QGIS + PostGIS installation: “the Windows way”

A short time ago I’ve posted an article on the installation of QGIS in combination with a PostGIS database in the background. As we all know, Windows is mostly used as OS on a PC so this is the Windowized version. This is a short summary that sums up the article of a site called Boston GIS. I’ll show you how to install QGIS version 1.8 (which will be updated in some days) and PostgreSQL with PostGIS extension and show you the first steps in the import of shapefiles and raster data.

Geodatabases: a little insight

Most GIS-users I know don’t use Geodatabases. But as your project may grow, participation and co-working gets more and more usual in your projects and you would like to share not only your results but also your data the usage of geodatabases will be one thing to keep in mind. Normaly each feature or raster is stored in separate files and maybe folders as well. This concept will stay alive in a geodatabase but in a more professional way: ArcGIS gives you the possibility to store your features in a file geodatabase, perosnal geodatabase or an ArcSDE Geodatabase. So what…