查詢用戶：
    select User from user;
    
授權權限：
    授予指定權限：
    grant insert,select on *.* to ‘user_name‘@‘localhost‘ with grant option; (*.*的意思：如：A.B => 數據庫A中的表B)
    授予所有權限：
    grant all privileges on *.* to ‘user_name‘@‘localhost‘ with grant option;
        
查看權限：
    show grants for ‘user_name‘
 
@‘localhost‘;
    查看當前用戶的權限：show grants;
    
回收權限：
    回收指定權限：
    revoke insert,select,grant option on *.* from ‘user_name‘@‘localhost‘ ...;
    回收所有權限：
    revoke all privileges,grant option from ‘user‘@‘localhost‘ ...;
    
    
    grant insert,select on *.* to ‘zhangsan‘@‘localhost‘ with grant
 
 option;
    show grants for ‘zhangsan‘@‘localhost‘;

mysql-權限管理