如果结果是正数和负数，如何从多列中求和并分离到单独的列中

Question

我正在使用 postgresql，需要编写一个查询来对来自两个不同表的不同列的值求和，然后如果是正数或负数，则将它们分成单独的列。

例如，

下面是源表

下面是需要创建的结果表，在填充时也要使用它

我在下面编写了查询以汇总总和并能够填充 TOT_CREDIT 和 TOT_DEBIT 列。是否有任何优化的查询来实现这一点？

select  t.account_id,
        t.transaction_date,
        SUM(t.transaction_amt) filter (where t.transaction_amt >= 0) as tot_debit,
        SUM(t.transaction_amt) filter (where t.transaction_amt < 0) as tot_credit,
        case
        when
        (
            SUM(t.transaction_amt) + 
            SUM(COALESCE(b.credit_balance,0)) +
            SUM(COALESCE(b.debit_balance,0))
        ) < 0
        then
        (
            SUM(t.transaction_amt) + 
            SUM(COALESCE(b.credit_balance,0)) +
            SUM(COALESCE(b.debit_balance,0))
        )
        end as credit_balance,
        case
        when
        (
            SUM(t.transaction_amt) + 
            SUM(COALESCE(b.credit_balance,0)) +
            SUM(COALESCE(b.debit_balance,0))
        ) > 0
        then
        (
            SUM(t.transaction_amt) + 
            SUM(COALESCE(b.credit_balance,0)) +
            SUM(COALESCE(b.debit_balance,0))
        )
        end as debit_balance,
from 
    transaction t   

LEFT OUTER JOIN balance b ON (t.account_id = b.account_id 
                                        and t.transaction_date = b.transaction_date 
                                        and b.transaction_date=t.transaction_date- INTERVAL '1 DAYS')
group by
    t.account_id,
    t.transaction_date

请指点一下。

编辑 1：此查询未按预期方式工作。

Answer 1

一种方法是将您的逻辑分解为小查询并最终加入它们！

select tw.account_id, tw.t_date,tw.t_c,th.T_D,fo.C_B,fi.d_B from 
(select account_id, Transaction_date as t_date, sum(Transaction_AMT) as t_C from TransactionTABLE 
where Transaction_AMT<0 group by  account_id, Transaction_date ) as tw inner join
(select account_id, Transaction_date as t_date, sum(Transaction_AMT) as t_d from TransactionTABLE 
where Transaction_AMT>0 group by  account_id, Transaction_date ) as th on tw.account_id=th.account_id and tw.t_date=th.t_date inner join
(select account_id, Transaction_date as t_date, sum(Transaction_AMT) as C_B from TransactionTABLE 
where sum(Transaction_AMT)<0 group by  account_id, Transaction_date ) as fo on th.account_id=fo.account_id and th.t_date=fo.t_date inner join
(select account_id, Transaction_date as t_date, sum(Transaction_AMT) as d_B from TransactionTABLE 
where sum(Transaction_AMT)>0 group by  account_id, Transaction_date ) as fi on fi.account_id=fo.account_id and fi.t_date=fo.t_date; 

否则

您可以尝试以下方法来计算 d_B 在 Transaction_date 和 account_id 上的运行计数

select  account_id,
        transaction_date,
        SUM(transaction_amt) filter (where transaction_amt >= 0) as tot_debit,
        SUM(transaction_amt) filter (where transaction_amt < 0) as tot_credit,
sum(transaction_amt) over (partition by account_id where sum(transaction_amt)<0) as credit_balance,
sum(transaction_amt) over (partition by account_id where sum(transaction_amt)>=0) as debit_balance
from TransactionTABLE group by account_id, Transaction_date order by 1,2;