T-SQL Script: Kill all sessions for a database

DECLARE @DBName NVARCHAR(50) = 'MyDatabase';
DECLARE @SQL NVARCHAR(MAX) = '';

SELECT @SQL += 'KILL ' + CAST(session_id AS NVARCHAR(10)) + ';'
FROM sys.dm_exec_sessions
WHERE database_id = DB_ID(@DBName);

EXEC(@SQL);