column "ms.xxx_time" must appear in the GROUP BY clause or be used in an aggregate function

------------------------------------------------------------------------------------------

有min(), max(), sum(), avg()这些函数可以和group by 语句连在一起用。

The SQL GROUP BY statement is used along with the SQL aggregate functions like SUM to provide means of grouping the result dataset by certain database table column(s).

【理解】column must appear in the GROUP BY clause or be used in an aggregate function