Joker character to allow everyone in a SQL table

Hello all ! I'm using a FreeRadius server 1.1.3. It is configured to use a SQL table (which contains some mac addresses to allow user to access to the network or not). This night the SQL table has flushed. Is there some joker characters I can put in the SQL table to allow everyone while I build up the table again ? Or any other way to do that ? Regards, Dav