Horst and I are spending the week up in Johannesburg at the Satellite Applications Center in Hartebeeshoek. We are doing yet another week long training course (I hope I’m not working the poor guy too hard ). This time we are doing: – Two days QGIS (with a little GRASS) – One day PostGIS -… Read more »
I have a cron job that backs up my PG databases and emails them to me everynight. Today I wanted to upgrade my PostgreSQL 8.3 databases to PG 8.4 so I made a few modifications to my script so that I could dump out my PG data, and then restore it under PG 8.4. In… Read more »
Hi, I’m Sam. I’ve been learning a lot here at Linfiniti (thanks to the brilliant team!) Just like to add a quick note on one of the tasks I learnt this week. I was working on a shapefile of the suburbs in Cape Town. A client required the suburbs to be grouped by region. After… Read more »
I’ve posted this before on my old blog so this is a repeat for those looking to get going with PostGIS in a hurry. This procedure should work on Ubuntu Jaunty or Ubuntu Karmic and possibly earlier versions. sudo apt-get install postgresql-8.3-postgis sudo su – postgres createuser -s -d -r -l -P -E timlinux createdb… Read more »
So you have moved your spatial data into PostGIS and everything is great….until you start wanting to clip it out again. Luckily clipping data within the postgres environment is trivial with the little help of SQL. However I wanted something a little more fancy – a way to iterate through all my spatial tables and… Read more »
Sometimes just because a thing is possible doesn’t make it a good idea. In the last week I have been helping a client whose web developer has dissapeared. The developer implemented the database using a variation on the Entity Attribute Value (EAV) modelling paradigm. The database consists of only four tables: Entities, Attributes, Values, EntityTypes…. Read more »
Someone asked on twitter it is possible to dump all the tables in Postgres to individual shp files. Some time ago I wrote a script to dump all tables as SQL dumps. The question prompted me to tweak that script to drop out shapefiles instead. My original script looked like the listing below. The dump… Read more »
Ok so I have a few production databases that I need to back up regularly. The trick is I want to run the backup from a remote machine so that the backup lives on a separate server to the actual database system. You can run backups manually like this (assuming your database is called ‘postgis’):… Read more »
Good news if you are a PostGIS fan – the PostGIS team just released version 1.4! See the release announcement for full details…