Shink log file in sql server 2008 r2

​USE alphago;

GO  -- Truncate the log by changing the database recovery model to SIMPLE.  ALTER DATABASE AdventureWorks2008R2  
SET RECOVERY SIMPLE;  GO  -- Shrink the truncated log file to 1 MB.  
DBCC SHRINKFILE (alphago_Log, 1);  GO  -- Reset the database recovery model.  ALTER DATABASE alphago  SET RECOVERY FULL;  GO

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