请教一条SQL语句的写法

Question

select mainID,min(lineC),max(LineCAmount),min(lineV),sum(lineVamount) as Vamount
from LineSun 
where mainid='20141221'
group by mainID

Answer 1

你这数据代表性不够
如果数据是这样，你的期望结果是什么样的
---------------------------------------------------------------
mainID              lineC     LineCAmount       lineV    LineVamount
20141221         1.1                  2                    2.2                2
20141221          2.2                 1                    2.2                4
20141222         1.1                  2                    2.2                2
20141222         2.2                  2                    2.2                4
20141222          3.3                 1                    2.2                8
---------------------------------------------------------------