Combining data ingest and Union actions

When you have multiple data sources that need to be vertically stacked using a union, you may opt to perform that action during ingestion. This avoids you having to create a separate Union step in Tableau Prep. Furthermore, you can use wildcards in your input, such that the input becomes dynamic, and new data files can be ingested as they are added. A typical scenario for this would be an automated process that exports data on a recurring schedule, which you then need to union with prior data exports.

In this recipe, we'll use a special type of union that is part of the input step, rather than a step by itself. Using the Union functionality during input allows you to ingest and union multiple input files simultaneously.

Getting ready

To follow along with this recipe, download the Sample Files 5.2 folder from this book's GitHub repository. This folder contains sales data that has been exported every month, and so we have one...