If I can give myself in the past a piece of advice about Tableau, that would be to use crosstab. This is especially the case when you have a lot of calculations going on in your Tableau workbook.
During those days preparing for the Data School application, I often found myself spending hours trying to understand why tableau didn’t do what I intend it to do. The reason for any kind of problem like that usually lies in the wrong table calculation.
WHY IS IT IMPORTANT
Using WORKOUT WEDNESDAY WEEK43 CHALLENGE as an example, the Sales by City (LOD: CITY) is showing the wrong calculation because there are two cities called Arlington, one in Virginia, another one in Texas.
This kind of problem can be easily spotted or checked using Crosstab as above. However, this is not known to a lot of new Tableau users.
HOW TO CREATE CROSSTAB
The easiest one is to right click your worksheet and select duplicate as a cross tab.
However, if you want to have better control of your crosstab results, it might be a better idea to really understand how to form a crosstab.
Here, I am still using the WORKOUT WEDNESDAY dataset as an example.
Step 1, drag any dimensions you want to inspect to Rows or Columns. The reason to drag instead of double click the dimensions is because data types like Geographic Role will directly turn your worksheet into a map after double click.
Step2, drag or double click one measure values to the worksheet.
Step 3, drag any other measures into the workbook.
Notice in the picture below, Measure Values and Measure Names appeared. Now you can drag or double click more measures into your workbook and start inspecting your calculation.
In conclusion, crosstab is really your best friend when it comes to designing informative visualization. If you are a Tableau beginner, I highly recommend you to have a try and start applying it in your work as early as possible.