SQL Server Table Reports Disk Usage 0 Rows but reserved 46 GBs I've executed report on database "Disk Usage by Table"
And I have couple of weird tables, where there are no rows, but disk used couple dozens of gigabytes.
What caused such behavior? What to do with this?
The solution is to TRUNCATE TABLE table_name instead of  DELETE FROM table_name.

P.S.
This tables are stage table and ETL uses them quite often, every 20 minutes data is inserted and shortly after data was processed - deleted.