SELECT db.database_id, 
       db.name, 
       GETDATE() datewhen, 
       db.log_reuse_wait_desc, 
       su.total_log_size_in_bytes * 1.0 / 1024 / 1024 [log_space_mb], 
       su.used_log_space_in_bytes * 1.0 / 1024 / 1024 [used_space_mb], 
       su.used_log_space_in_percent, 
       su.log_space_in_bytes_since_last_backup * 1.0 / 1024 / 1024 AS [written_since_backup_mb]
FROM sys.databases db
     INNER JOIN sys.dm_db_log_space_usage su ON su.database_id = db.database_id;