Can a table be partitioned in two ways?
For example, both with date and with the unit
````
if unit=1 and date > 2021-09-01 save rows in file1.ndf
if unit=1 and date > 2021-10-01 save rows in file2.ndf
if unit=2 and date > 2021-09-01 save rows in file3.ndf
if unit=2 and date > 2021-10-01 save rows in file4.ndf
````