How to sum from multiple columns and segregate into separate column if result is positive and negative - sql

Question

I am using postgresql and need to write a query to sum values from separate columns of two different tables and then segregate into separate columns if positive or negative.
For Example,
Below is the source table
Below is the resultant table which need to be created also used while populating it
I have written below query to aggregate sum and able to populate TOT_CREDIT and TOT_DEBIT column. Is there any optimized query to achieve that ?
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
Please provide some pointer.
EDIT 1: This query is not working in expected manner.

Answer 1

One way is to break your logic into smal queries and join them in the end!
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;
Or else
You could try something as follows which calculates the running count of d_B over the Transaction_date and account_id
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;