Hive 配置单元SQL-条件计数

我在这个条件计数中遇到了一个问题，被困在这里一天了！希望能从大家这里找到解决办法。 所以我有一个等级表，它有三列： 1.大主题 2.主题（这是大主题的细分） 3.等级

所以，我想做的是，我要计算一个大的科目和每个科目的分数{A分数百分比=多少A除以A加B的分数（多少A/（多少A+多少B）*100%}。有两个规则适用如下：1）。对于这两大主题：离散数学和统计学，分数计算应结合为数学；但是，对于其他大科目将单独计算（物理、历史） 2). 对于“科目”列，应分别计算每个科目的成绩

预期输出如下所示：

                                         A_Grade_Percentage
-----------------------------------------------------------------
    Maths (Discrete Math + Statistics)         54.50%
    Discrete Math 1                             50%
    Statistics 1                                60%
-----------------------------------------------------------------
    Physics                                   54.50%
    Physics Basic                               75%
    Physics 1                                   25%
    Physics 2                                 66.70%
-----------------------------------------------------------------
    History                                     50%
    History 1                                   50%
    History 2                                   50%
-----------------------------------------------------------------
    Geography                                   25%

到目前为止，我已经尝试了以下长代码：

with on_grand_subject as(
select
case when grand_subject in ('Discrete Math', 'Statistics') then 'Maths'
     else grand_subject end as grand_subject,
count(case when grade = 'A' then 1 else 0 end) as A_Grade,
100.0*count(case when grade = 'A' then 1 else 0 end) / 
   (count(case when grade = 'A' then 1 else 0 end) + count(case when grade = 'B' then 1 else 0 end)) 
   as A_Grade_percentage,
from
grade_table
where
 ...................
group by grand_subject in ('Discrete Math', 'Statistics') then 'Maths' else grand_subject end
order by grand_subject
limit 1000
),

on_subject as(
select
grand_subject,
subject,
count(case when grade = 'A' then 1 else 0 end) as A_Grade,
100.0*count(case when grade = 'A' then 1 else 0 end) / 
   (count(case when grade = 'A' then 1 else 0 end) + count(case when grade = 'B' then 1 else 0 end)) 
   as A_Grade_percentage,
from
grade_table
where
 ...................
group by grand_subject, subject
order by subject
limit 1000
)

select
g.grand_subject, s.subject, g.A_Grade, g.A_Grade_percentage, s.A_Grade, g.A_Grade_percentage
from on_grand_subject g join on_subject s on g.grand_subject = s.grand_subject

---

但是输出看起来很奇怪，不是它应该是什么。有什么解决办法吗？非常感谢

这是错误的：

count（当等级为'A'时，则为1，否则为0结束）

因为count也将计算1和0。它应该是sum（）而不是count。或者删除

else 0

或

else null

如果您以方便的形式发布文本，而不是图片，您获得答案的机会会更好。目前，除了使用手动输入，您的数据集无法复制。@leftjoin啊！对我忘了用sum（），过去用count（）。。那我就试试sum（）了，顺便说一句，我用方便的形式编辑了这个问题，谢谢你的建议！更好，但仍然需要一些工作才能获得正常的数据集。这可能会有帮助：

with on_grand_subject as(
select
case when grand_subject in ('Discrete Math', 'Statistics') then 'Maths'
     else grand_subject end as grand_subject,
count(case when grade = 'A' then 1 else 0 end) as A_Grade,
100.0*count(case when grade = 'A' then 1 else 0 end) / 
   (count(case when grade = 'A' then 1 else 0 end) + count(case when grade = 'B' then 1 else 0 end)) 
   as A_Grade_percentage,
from
grade_table
where
 ...................
group by grand_subject in ('Discrete Math', 'Statistics') then 'Maths' else grand_subject end
order by grand_subject
limit 1000
),

on_subject as(
select
grand_subject,
subject,
count(case when grade = 'A' then 1 else 0 end) as A_Grade,
100.0*count(case when grade = 'A' then 1 else 0 end) / 
   (count(case when grade = 'A' then 1 else 0 end) + count(case when grade = 'B' then 1 else 0 end)) 
   as A_Grade_percentage,
from
grade_table
where
 ...................
group by grand_subject, subject
order by subject
limit 1000
)

select
g.grand_subject, s.subject, g.A_Grade, g.A_Grade_percentage, s.A_Grade, g.A_Grade_percentage
from on_grand_subject g join on_subject s on g.grand_subject = s.grand_subject