出现User 1055 - Expression #2 of SELECT list is not in GROUP BY clause and contains nonaggregated 解决方法

1. 问题所示

执行Sql的时候，出现如下问题

1055 - Expression #2 of SELECT list is not in GROUP BY clause and contains nonaggregated 
column 'easy-admin.students.age' which is not functionally dependent on columns in GROUP BY clause; 
this is incompatible with sql_mode=only_full_group_by

截图如下：