A. Shrinking a data file to a specified target size
The following example shrinks the size of a data file named DataFile1 in the UserDB user database to 7 MB.
USE UserDB; GO DBCC SHRINKFILE (DataFile1, 7); GO
B. Shrinking a log file to a specified target size
The following example shrinks the log file in the AdventureWorks database to 1 MB. To allow the DBCC SHRINKFILE command to shrink the file, the file is first truncated by setting the database recovery model to SIMPLE.
USE AdventureWorks2012; GO -- Truncate the log by changing the database recovery model to SIMPLE. ALTER DATABASE AdventureWorks2012 SET RECOVERY SIMPLE; GO -- Shrink the truncated log file to 1 MB. DBCC SHRINKFILE (AdventureWorks2012_Log, 1); GO -- Reset the database recovery model. ALTER DATABASE AdventureWorks2012 SET RECOVERY FULL; GO
C. Truncating a data file
The following example truncates the primary data file in the AdventureWorks database. The sys.database_files catalog view is queried to obtain the file_id of the data file.
USE AdventureWorks2012; GO SELECT file_id, name FROM sys.database_files; GO DBCC SHRINKFILE (1, TRUNCATEONLY);
D. Emptying a file
The following example demonstrates the procedure for emptying a file so that it can be removed from the database. For the purposes of this example, a data file is first created and it is assumed that the file contains data.
USE AdventureWorks2012; GO -- Create a data file and assume it contains data. ALTER DATABASE AdventureWorks2012 ADD FILE ( NAME = Test1data, FILENAME = 'C:\t1data.ndf', SIZE = 5MB ); GO -- Empty the data file. DBCC SHRINKFILE (Test1data, EMPTYFILE); GO -- Remove the data file from the database. ALTER DATABASE AdventureWorks2012 REMOVE FILE Test1data; GO
https://docs.microsoft.com/en-us/sql/t-sql/database-console-commands/dbcc-shrinkfile-transact-sql