USE master
GO
DECLARE @kill varchar(8000) ; SET @kill = ''
SELECT @kill = @kill + 'KILL ' + CONVERT(varchar(5), spid) + ';'
FROM master..sysprocesses
WHERE dbid IN
(
db_id('databaseName')
, db_id('anotherDataBase')
)
IF @kill = ''
PRINT 'No connection found.'
ELSE
EXEC (@kill) -- le parentesi servono!
Testato su SQL2005. Basato sullo script trovato qui.