...ofcourse you do...
first make a char with desired name then exit the game
open SQL server manager/database/character/tables/user_character then right click on user_character/open table/return all rows then search for you char by name once you find him just add [GM] before his name (example if your char name is Kakkarot you add [GM]Kakkarot like that) and hit RUN, now log back ingame and you're a GM