How to disable 'ONLY_FULL_GROUP_BY' ?

Hello I want to disable set global sql_mode = (select replace(@@sql_mode,'ONLY_FULL_GROUP_BY', '')); but when i paste it into SQL then i receive this error : Error SQL query: set global sql_mode = (select replace(@@sql_mode,'ONLY_FULL_GROUP_BY', '')) MySQL said: #1227 - Access denied; you need (at least one of) the SUPER privilege(s) for this operation Please help,how to grant privileges? Sincerely