checa este mensaje, hace referencia e esta pagina
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grant all on (database_name).* to (user)@(hostname) identified by '(password)';
this is the command you need. The parenetheses are not needed, I use them to indicate where you have to put in your specific values. If you are just running one machine you can use localhost for you hostname.
If you need further info on the GRANT command. RTFM.