use master
go

declare @dbname sysname
set @dbname = 'testdb' --要删除的数据库名

declare @s nvarchar(1000)
declare tb cursor local
for
  select s = 'kill   ' + cast(spid as varchar)
  from master.dbo.sysprocesses
  where dbid = DB_ID(@dbname)
open tb
fetch next from tb into @s
while @@fetch_status = 0
begin
  exec (@s)
  fetch next from tb into @s
end
close tb
deallocate tb

exec ('drop database [' + @dbname + ']')