Clearly and Simply

Calculated Fields in Tableau

How to create and use Calculated Fields in Tableau Software, illustrated with a show case of a site analysis for Germany

As soon as your data analyses and visualizations with Tableau Software become more complex, you will soon find that sometimes your data source does not include all the measures and dimensions you need.

One of the most common examples is a data set including the measures revenues and costs, but lacking a profit field.

This is where Tableau’s Calculated Fields come into play. This functionality enables you to add new fields based on dimensions and measures from your data source and/or based on other Calculated Fields.

If you are interested in professional data analysis and visualizations using Tableau Software, you definitely won’t get out of using Calculated Fields sooner or later.

Today’s post discusses the power of Tableau’s Calculated Fields, including a definition, a short how-to tutorial and a few additional tips. A show case of a site analysis for Germany illustrates the use of different types of Calculated Fields including the Tableau packaged workbook for free download. 

Geocoding Databases for Europe

Databases including latitudes and longitudes of cities and postcodes of most European countries for free download

Soon after publishing Tableau Custom Geocoding outside the US and UK, I received a very interesting email from Richard van Dijk. Richard obviously liked yesterday’s article and he is kind and generous enough to share great geographical databases of European cities and postcodes with us. See a Tableau visualization of the postcodes on a European map in the screenshot left. The databases include the geographical data of more than 250,000 European cites and more than 296,000 postcodes.

Richard pulled this data out of a 2009 download from geonames.org. With a little help from the Tableau Support team he converted these downloads into geocoding databases accessible with Tableau Software.

Here is a zipped folder including both databases as CSV files in US standard (point as decimal separator, comma as field separator) for free download:

Download European Cities and Postcodes US Standard (zipped folder, 3638.3K)

And here is the same data using the European standard (comma as decimal separator, semicolon as field separator):

Download European Cities and Postcodes EU Standard (zipped folder, 3638.5K)

Please be advised that the data does not cover all countries in Europe: Ireland, Greece, Bosnia and Herzegovina, Romania, Serbia, Montenegro, Albania, Ukraine, Belarus and the Baltic States are not included. Furthermore there seem to be some smaller inaccuracies in the European city database. Have a closer look at Spain or Italy for instance.

Nevertheless, these databases are enormously helpful if you want to import Custom Geocoding into Tableau Software and create a higher level of detail in your geographical visualizations of Europe.

Many thanks again, Richard. Your contribution is highly appreciated.

Please visit also Richard’s profile on LinkedIn and follow him on Twitter.

Finally, may I ask you a favor? If you like Richard’s data and find it useful for your own work, I would highly appreciate if you could drop him a line in a comment here to say thank you for sharing. We shouldn’t take it like a duck to water that Richard is so generous to share his work with us.

Tableau Custom Geocoding outside the US and UK

How to properly import a custom geocoding into Tableau for countries outside the US and the UK

I am using Tableau for more than 3 years now and I am living in Germany. To my own surprise I noticed these days that I never used the Import Custom Geocoding feature of Tableau Software. Don’t ask me why. I always had the latitudes and longitudes in the underlying database, I guess.

A couple of days back, however, a colleague of mine asked for my assistance. He tried to make German postcodes available as a new geographic role in Tableau Software by using Custom Geocoding. He hit a roadblock: it simply didn’t work.

Thus, I had a look at this feature for the very first time and I faced the same problem: I couldn’t manage to properly import the data. More precisely: I couldn’t import the Custom Geocoding at all!

Even following a step-by-step tutorial described in the Tableau Knowledge Base (Importing Numeric Geographical Roles) led to the same issue: no import of the Custom Geocoding possible. Problems like this simply drive me nuts. After digging deeper into this, I finally found the root cause of the problem and a solution.

Today’s post describes how to properly import Custom Geocoding data in Tableau Software, if you are living outside of the US and the UK. The article is based on the example of German postcodes (“Postleitzahlen”, “PLZ2” and “PLZ5”), but the technique should be applicable to any other data set as well.