TRUNCATE_ONLY is not a recognized BACKUP option

Executing the code below in SQL Server 2008 will throw an error message:

BACKUP LOG ‘MyDatabase’ WITH TRUNCATE_ONLY

Msg 155, Level 15, State 1, Line 44
'TRUNCATE_ONLY' is not a recognized BACKUP option.

It was deprecated in SQL Server 2008.To view SQL deprecated features use the Perfmon SQL Server Deprecated Features Object  

 Some options for SQL Server 2008 are :

 1)    BACKUPLOG [DBNAME] TODISK='NUL'

This will break the  transaction log chain. Therefore a Full backup is required after the command.

2)    Switch to Simple Recovery and then switch back to Full Recovery. This will required a Full backup to restart a new  transaction log chain

 3)  DBCC SHRINKFILE(Test_Log)    . This option causes fragmentation , but does the job when it comes to reclaiming space.   You might find it doesn’t shrink – in that case check for open transactions.

4) Take regular Transaction Log backups while maintaining a small log file size

 The choice will depend on the circumstances.

Read More on Transaction Logs Management

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