How to select one column to display as 2 columns result with difference value in Postgresql

Question

I got problem on query one column with difference value to display in 2 column result in PosgrestSql. The showing value mean outstanding, for the showing 0 mean already paid. And need to show all pending column and count the already paid in new column. I have tried many query but couldn't find.

My first query as below: first query

And then I need the result as below: I need the result

And for my new query that I try as below:

SELECT
  m.customercd,
  ta.agreementcd,
  (SELECT
    (tcd.balanceprincipal + tcd.balanceinterest + tcd.balanceapprovalfeeprincipal)
  FROM t_agreement ta
  INNER JOIN t_creditdetail tcd
    ON ta.agreementcd = tcd.agreementcd
  WHERE (tcd.balanceprincipal + tcd.balanceinterest + tcd.balanceapprovalfeeprincipal) != 0)
  AS Installment,
  (SELECT
    (tcd.balanceprincipal + tcd.balanceinterest + tcd.balanceapprovalfeeprincipal)
  FROM t_agreement ta
  INNER JOIN t_creditdetail tcd
    ON ta.agreementcd = tcd.agreementcd
  WHERE (tcd.balanceprincipal + tcd.balanceinterest + tcd.balanceapprovalfeeprincipal) = 0)
  AS Installment_PAID,
  m.corpname,
  m.employeenum
FROM t_agreement ta
INNER JOIN t_creditdetail tcd
  ON ta.agreementcd = tcd.agreementcd
INNER JOIN m_customer m
  ON ta.customercd = m.customercd
WHERE ta.agreementcd IN ('1502-0004759-9', '1506-0006177-9', '1506-0006327-8')
ORDER BY agreementcd

But still got error:

ERROR: more than one row returned by a sub query used as an expression

So are there any expert to help me on this? Would be very appreciate with your help.

Thank you very much, SmallCorner

Answer 1

Alright I had to break out each query to understand what is going on so here is effectively your main query with the sub queries removed and replaced w/ comments

main query

select
  m.customercd,
  ta.agreementcd,
  # installment sub query
  # installment paid sub-query
  m.corpname,
  m.employeenum
from t_agreement ta
  JOIN t_creditdetail tcd ON ta.agreementcd = tcd.agreementcd
  JOIN m_customer m ON ta.customercd = m.customercd
where  ta.agreementcd in ('1502-0004759-9','1506-0006177-9','1506-0006327-8')
order by agreementcd;

unpaid installments

select
  tcd.balanceprincipal + tcd.balanceinterest  + tcd.balanceapprovalfeeprincipal AS installment
from t_agreement ta
  JOIN t_creditdetail tcd ON ta.agreementcd = tcd.agreementcd
where
  (tcd.balanceprincipal + tcd.balanceinterest  + tcd.balanceapprovalfeeprincipal) != 0;

paid installments

select
  tcd.balanceprincipal + tcd.balanceinterest  + tcd.balanceapprovalfeeprincipal as installment_paid
from t_agreement ta
JOIN t_creditdetail tcd ON ta.agreementcd = tcd.agreementcd
where
  (tcd.balanceprincipal + tcd.balanceinterest  + tcd.balanceapprovalfeeprincipal) = 0;

I removed INNER JOIN since it is the same as JOIN . You should do your best to avoid using subqueries (added complexity, performance issues) but if you have to use them (I have to countless times at work) you should run them on their own to see what results they are returning. In your case I don't think you could of even used subqueries in the select statement as they need to be tied back to your agreemendcd. You would have to use them as joins. Either way this answer should work.

answer

select
  m.customercd,
  ta.agreementcd,
  tcd.balanceprincipal + tcd.balanceinterest + tcd.balanceapprovalfeeprincipal AS balance,
  m.corpname,
  m.employeenum
from t_agreement ta
  JOIN t_creditdetail tcd ON ta.agreementcd = tcd.agreementcd
  JOIN m_customer m ON ta.customercd = m.customercd
where
  ta.agreementcd in ('1502-0004759-9','1506-0006177-9','1506-0006327-8')
  and (tcd.balanceprincipal + tcd.balanceinterest  + tcd.balanceapprovalfeeprincipal) != 0  # unpaid balances
order by agreementcd;