/*
Since you cant alter the database straight away, you first need to kill the user thats currently connected to it...
So...
Step 1:
Get the session thats connected to that database
*/
 
select d.name, d.dbid, spid, login_time, nt_domain, nt_username, loginame
from master.dbo.sysprocesses p inner join master.dbo.sysdatabases d on p.dbid = d.dbid
where d.name = 'DATABASE NAME GOES HERE'