如何对一些值求和并将其分组在mysql中

Question

我有这样的Table A：

我想要这样的结果查询：

我该如何实现？

Answer 1

我认为您的总结果可能是45。结果75是从哪里来的？我不清楚。如果要45，可以使用以下查询

    select case When a.Item IS NULL THEN 'total' Else  a.Item  END AS Item,sum(a.value) as value from
     (select Item,sum(value) as value from test1 as t1 where t1.Item='A' or t1.Item='B'   group by  t1.Item )
    as a group by a.Item WITH ROLLUP