In Alteryx, which tool is used primarily for combining two data streams?

The Join tool is primarily used for combining two data streams based on a key or common field. It allows you to merge datasets by aligning them based on specified join conditions, which can be inner, outer, left, or right joins. This is particularly useful when you need to consolidate information from two different sources that share one or more common attributes. The Join tool effectively creates a new output that includes combined fields from both datasets, making it valuable for data preparation and analysis.

In contrast, the Union tool is designed to stack data vertically from two or more streams, which is different from the kind of joining that the Join tool performs. The Append Fields tool adds fields from one dataset to another without any condition on the matching keys, essentially padding records but not combining based on relationships. The Filter tool is used to separate data based on specific criteria rather than combining data streams. Each of these tools serves different purposes in data manipulation and is optimized for specific tasks within Alteryx workflows.