一个应用问题，请帮忙看看select f.a,sum(xyCount)from(select f.a,count(distinct(ly.b)) xyCountfrom f i
一个应用问题，请帮忙看看
select f.a,sum(xyCount)
from
(select f.a,count(distinct(ly.b)) xyCount
from f inner join ly on ...
group by f.a
union
select f.a,count(distinct z.b) xyCount
from f inner join z on ...
group by f.a
)
group by a
两个使用了聚合函数的结果及并集后再group by，这样写有错误
有什么好办法吗？
[最优解释]
select a,sum(xyCount)
from
(select f.a,count(distinct(ly.b)) xyCount
from f inner join ly on ...
group by f.a
union
select f.a,count(distinct z.b) xyCount
from f inner join z on ...
group by f.a
) as TB
group by a
[其他解释]select f.a,sum(xyCount)
from
(select f.a,count(distinct(ly.b)) xyCount
from f inner join ly on ...
group by f.a
union
select f.a,count(distinct z.b) xyCount
from f inner join z on ...
group by f.a
) a
group by a
加个红字
[其他解释]select f.a,sum(xyCount) xyCount
from
(select f.a,count(distinct(ly.b)) xyCount
from f inner join ly on ...
group by f.a
union
select f.a,count(distinct z.b) xyCount
from f inner join z on ...
group by f.a
) as B
group by a
绿色的地方去掉，红色的地方加上
[其他解释]“绿色的地方去掉，红色的地方加上 ”。
谢谢！
[其他解释]派生表需要有一个名称，否则会报错
