Patch SQL Server

Hi all,

i have some questions around patching BizTalk 2010 or SQL Server 2008 (the message box or others).

if i patch sql server 2008 sp1 (a patch or another SP, the sp2), do i need to restart the sql server ? will the message box stop ? is there a scenario to avoid this behavior, i mean an architecture where BizTalk is not interrumpted  ?

same question if i want to upgrade from sql server 2008 sp1 to sql server 2008 r2, how i can upgrade without stop BizTalk service ? or the minimum time possible.

Thanks