Use the Command Window to run commands, such as debug and edit commands, against the code in the SQL Server Database Engine Query Editor window that is currently being debugged. You must be in debug mode to use the Command Window. The Transact-SQL debugger supports many of the commands that are also supported in the Microsoft Visual Studio Command window. For more information, see Visual Studio Command Window.
To access the Command Window
On the Debug menu, click Start Debugging.
To print the value of a variable
In the Command Window, type Debug.Print <VariableName>, and then press ENTER.
To list information about the current thread
In the Command Window, type Debug.ListThread, and then press ENTER.
To add a variable to the QuickWatch window
In the Command Window, type Debug.QuickWatch <VariableName>, and then press ENTER.