I look at some databases people tend to ignore:
Today is a fairly short post covering a trio of databases you might not even know you have: DWConfiguration, DWDiagnostics, and DWQueue. The PolyBase installer drops all three of these on your instance. Let’s go in ascending order of the number of useful tables.
There are very few useful (to us) tables when using on-prem SQL Server as opposed to APS, but there are a few of note.