如何获取每个ID的正数和负数？

Question

我想计算每个 id 的负值和正值。

样品小提琴

ID=1 has 2 positive and 0 negative transactions. etc.

 with trans_detail as 
 (
 select 1 as trans_id, 100 as trans_amount  from dual union all
 select 1 as trans_id, 200 as trans_amount  from dual union all
 select 2 as trans_id, -100 as trans_amount  from dual union all
 select 2 as trans_id, -300 as trans_amount  from dual union all
 select 3 as trans_id, 400 as trans_amount   from dual union all
 select 3 as trans_id, -500 as trans_amount  from dual
 )

 select trans_id,
       count(*) over (partition by trans_id) as pos_count,
       count(*) over (partition by trans_id) as neg_count        
from trans_detail
where trans_amount > 0
UNION
select trans_id,
       count(*) over (partition by trans_id) as pos_count,
       count(*) over (partition by trans_id) as neg_count        
from trans_detail
where trans_amount < 0;

预期结果：

 ID   POS_COUNT   NEG_COUNT
---- ----------- -----------
 1    2           0 
 2    0           2
 3    1           1

Answer 1

每次看到正数或负数时数 1，然后将其相加。

select trans_id,
sum(case when trans_amount >=0 then 1 else 0 end) as pos_amt,
sum(case when trans_amount < 0 then 1 else 0 end) as neg_amt
from trans_detail
group by trans_id

http://sqlfiddle.com/#!4/db410/12