When creating a drag & drop table containg two metricsand each metric has a different unit, the most recently added metric will override the previous metrics.
For example:
In a drag & drop table where the second column's total had to be reported in TB in order to be displayed reasonably (7.2 TB rather than 7200 GB), the first column's total would also be reported in TB regardless of it's actual unit (MB/GB etc).