Set a Database to Single-user Mode with SQL Server Management Studio
Single-user mode specifies that only one user at a time can access the database and is generally used for maintenance actions.
This topic describes how to set a user-defined database to single-user mode by using Object Explorer in SQL Server Management Studio.
If other users are connected to the database at the time that you set the database to single-user mode, their connections to the database will be closed without warning.
The database remains in single-user mode even if the user that set the option logs off. At that point, a different user, but only one, can connect to the database.
To set a database to single-user mode in SQL Server
1) In Object Explorer, connect to an instance of the SQL Server Database Engine, and then expand that instance.
2) Right-click the database to change, and then click Properties.
3) In the Database Properties dialog box, click the Options page.
4) From the Restrict Access option, select Single.
5) If other users are connected to the database, an Open Connections message will appear. To change the property and close all other connections, click Yes.
You can also set the database to Multiple or Restricted access by using this procedure.
If you use SQL Server 2012, before you set the database to SINGLE_USER, verify that the AUTO_UPDATE_STATISTICS_ASYNC option is set to OFF. When this option is set to ON, the background thread that is used to update statistics takes a connection against the database, and you will be unable to access the database in single-user mode.
Using Transact-SQL To set a database to single-user mode (SQL Server 2012 only)
1) Connect to the Database Engine.
2) From the Standard bar, click New Query.
3) Copy and paste the following example into the query window and click Execute. This example sets the database to SINGLE_USER mode to obtain exclusive access. The example then sets the state of the AdventureWorks2012 database to READ_ONLY and returns access to the database to all users.The termination option WITH ROLLBACK IMMEDIATE is specified in the first ALTER DATABASE statement. This will cause all incomplete transactions to be rolled back and any other connections to the AdventureWorks2012 database to be immediately disconnected.
USE master; GO ALTER DATABASE DatabaseName SET SINGLE_USER WITH ROLLBACK IMMEDIATE; GO ALTER DATABASE DatabaseName SET READ_ONLY; GO ALTER DATABASE DatabaseName SET MULTI_USER; GO