-- Step 1: Set the DB in Single User Mode.
IF DATABASEPROPERTYEX (N'DBName', N'Version') > 0
BEGIN
ALTER DATABASE [DBName] SET SINGLE_USER
WITH ROLLBACK IMMEDIATE;
END
GO
-- Step 2: Rename the DB
EXEC sp_renamedb 'DBName', 'DBNameNew'
-- Step 3: Set the DB back in Multi User Mode.
IF DATABASEPROPERTYEX (N'DBNameNew', N'Version') > 0
BEGIN
ALTER DATABASE [DBNameNew] SET Multi_USER
WITH ROLLBACK IMMEDIATE;
END
GO