[RADIATOR] how to bind users with group?

[Ruchi Shah]

Hi,
     I have added user in users file like below.

     mikem    User-Password=fred
     Service-Type = Framed-User,
         Framed-Protocol = PPP,
         Framed-IP-Netmask = 255.255.255.255,
         Framed-Routing = None,
         Framed-MTU = 1500,
         Framed-Compression = Van-Jacobson-TCP-IP

     Now same way if i want bind user and group where should i write 
that and how?
     Is there any way possible without using SQL?

     If SQL is only the way then how to do it using SQL?

     Thanks in adnavced.

Regards,
     Ruchi Shah