Wildcard union
The first time you saw how to create unions, you had to select the different tables of the dataset that you wanted to use manually. Wildcard unions allow you to create more powerful unions that automatically add all the files and all the tables that match a specific pattern. This kind of union is convenient because you don't have to add the new tables manually; you only need to refresh the data source.
As an example of a wildcard union, I am going to split the Sample-Superstore
Excel file into four Excel files, one for each year, and put them in a folder named Sales
.
Note
To reproduce the following example, you need to download the Sales.
zip file from https://tableau2019.ladataviz.com, in the Chapter 11: Advanced Data Connections section, or use this link: https://ladataviz.com/wp-content/uploads/2018/09/Sales.zip.
Let's union those files:
- First, unzip the
Sales.zip
file you've just downloaded. - Open Tableau Desktop and chose Microsoft Excel from the list of...