更新时间:2022-11-25 21:00:43
The usage of GROUP BY
makes the engine group the records for you. To do grouping, you have to give advice to the RDBMS for each column, what it should do.
GROUP BY-Clause
SUM(mycol)
Additionally: In your case you try to group by EPS_ID
, which is unique in each row. So a grouping by that column will return all rows, because there is nothing to group by. To group records, they have to have the same value.