اشكال در سايز backup

[karimi84]

با سلام
وقتي از ديتابيس backup ميگيريم سايزش برابر است با 19950752 kb
ولي وقتي از گزارش از سيستم ميگيرم سايز backup را 63443180544 نشون ميده اين اختلاف براي چيه
در ضمن براي گزارش به تابع زير استفاده ميكنم

[karimi84]

SELECT TOP 100
s.database_name,
m.physical_device_name,
CAST(CAST(s.backup_size / 1000000 AS INT) AS VARCHAR(14)) + ' ' + 'MB' AS bkSize,
CAST(s.backup_size AS VARCHAR(14)) + ' ' + 'kb' AS kb,
CAST(DATEDIFF(second, s.backup_start_date,
s.backup_finish_date) AS VARCHAR(4)) + ' ' + 'Seconds' TimeTaken,
s.backup_start_date,
CAST(s.first_lsn AS VARCHAR(50)) AS first_lsn,
CAST(s.last_lsn AS VARCHAR(50)) AS last_lsn,
CASE s.[type]
WHEN 'D' THEN 'Full'
WHEN 'I' THEN 'Differential'
WHEN 'L' THEN 'Transaction Log'
END AS BackupType,
s.server_name,
s.recovery_model
FROM msdb.dbo.backupset s
INNER JOIN msdb.dbo.backupmediafamily m ON s.media_set_id = m.media_set_id
WHERE s.database_name = DB_NAME() -- Remove this line for all the database
ORDER BY backup_start_date DESC, backup_finish_date