Perhaps like a lot of Alteryx users the recent partnership between Alteryx and Tableau has meant my first exposure to Tableau, and so I’ve been getting my hands dirty since getting a licence. I love Tableau, it’s really intuitive and easy to use – and I can quickly build some simple visualisations. However there is also a learning curve, table calculations are tricky and will be the subject of a future post, and it’s not always obvious how to do what you want (even if it seems simple). Thankfully there’s a great community of bloggers and users who have filled the internet with information – so the answer is only a fingertip away.
However, one of the fundamental lessons about Tableau isn’t covered from what I’ve seen – it isn’t Excel! I experienced the lesson first hand this week when I had a question from a new user and I was struck by how different this user’s approach was – they were approaching the problem exactly like you would in Excel and getting the wrong answer.
Lets start with some example data:
Now lets start creating a table:
So far so good, but now what if we want the response rate. My colleague knew what he needed to do. New calculation, and divide the number of responses by the number of sends.
Then double-click to the add it to the table. His first Tableau calculation, sit back and smile.
My colleague had looked at the table as an Excel sheet and assumed the calculation in the third column would act on the two columns to it’s left, which it won’t. Hopefully you are well ahead of me here and can see that the calculation is calculating the response rate at the row level in the data (i.e. as a dimension), then summing it to give a completely wrong result (from his point of view).