Question

我已经完成了这个SQL，但我需要一些帮助来改变它

select id, (select sum(col1) from t1) as totalcol1, 
(select sum(col1) from t1 where id = 7) as total_for_id from t1
group by id

所以基本上我想总结每个id的col1，并总结col1为id = 7，所有这些都来自同一个表t1。我希望能够通过创建日期和逐月扩展此查询，并且每次尝试我都会保持获取太多值错误或子查询检索多行值。像

这样的东西

select (select to_char(view_date,'Mon-YY') from t1 group by to_char(view_date,'Mon-YY'))
as month, id, (select sum(col1) from t1 where view_date between '30-nov-2013' and '01-dec-
2013') as totalcol1, (select sum(col1) from t1 where id = 7 and view_date between '30-nov-2013' and '01-dec-2013')
as total_for_id from t1
group by id

我意识到这很糟糕，任何解决方案都会受到赞赏

对，我也可以显示它想要的输出

month --|- id --|--- sum(col1 where id = 7) --|---sum(col1)

nov-13  ---  7   --------------100---------------   1000

dec-13  ---  7  -------------- 200  --------------  1500

Answer 1

这是你想要的吗？

select to_char(view_date, 'Mon-YY'), 7 as id,
       sum(col1) as totalcol1, 
       sum(case when id = 7 then col1 else 0 end) as total_for_id7
from t1
group by to_char(view_date, 'Mon-YY')
order by min(view_date);

我添加了order by，因此结果将按日期顺序排列。您是否考虑过使用'YYYY-MM'这样的日期格式，也可以用于排序？

Answer 2

CASE是你的朋友。一直使用它来报告，但速度很慢。

Select sum(col1) as Total, 
  sum(Case When id=7 Then col1 Else 0 End) as TotalId7,
  ...
From t1

每月在同一个表的不同标准下对同一列进行两次求和

2 个答案: