use master  
go

create proc KillSpByDbName(@dbname varchar(20))
as
begin
declare @sql nvarchar(500),@temp varchar(1000)
declare @spid int
set @sql='declare getspid cursor for  
select spid from sysprocesses where dbid=db_id('''+@dbname+''')'
exec (@sql)
open getspid
fetch next from getspid into @spid
while @@fetch_status<>-1
begin
 set @temp='kill '+rtrim(@spid)
 exec(@temp)
fetch next from getspid into @spid
end
close getspid
deallocate getspid
end

Use master   
 Exec KillSpByDbName '数据库名称'