Immediately stop SQL Server.
Syntax
SHUTDOWN [WITH NOWAIT]
Issuing SHUTDOWN WITH NOWAIT or directly stopping the msSqlServer service from the Windows control panel will not perform a checkpoint. When the database is restarted, this will force a rollback operation to occur for any uncompleted transactions.
Example
SHUTDOWN
"It is now safe to turn off your computer" ~ Windows error message
Related commands:
CHECKPOINT
ALTER DATABASE
Equivalent Oracle command: SHUTDOWN