Hi,
you can see this in the output of your sql as "Data Full%" and "Log Full%". For the databases with separate data and log, so where you don't have any nulls, it does not make sense to calculate an overall filling level as data and log are completely different.
If the data area becomes full you have to increase the database. And if the log segment becomes full, you can empty it (either backup to a file or truncate). So it makes sense to monitor the values independently and trigger different actions.
Best regards,
Juergen