UI-Based Data Blending (Cross-Dataset Joining in Explore)

What is the problem or goal you're trying to solve or accomplish?

The user wants to visualize data from two different datasets (one physical table, one virtual dataset) on a single chart by joining them on a shared dimension (e.g., month). Currently, Superset forces a 1:1 relationship between a chart and a datasource. The user is looking for functionality similar to Looker's "Merged Results," where distinct views can be joined at the visualization layer without modifying the underlying SQL or schema.

How are you solving it currently?

The user has to manually write SQL in a new Virtual Dataset to JOIN the physical table and the virtual query logic together. This is difficult if the user is not proficient in SQL or if the datasets reside in different databases (which requires complex federation workarounds).

What is your recommended solution?

Provide an option in the Chart Builder (Explore) to select a secondary dataset and define a join key (e.g., "Join on month") to merge results into a single visualization dynamically.