Question

i am joining two tables: accn_demographics and accn_payments. The relationship between the two tables is one to many between accn_demographics.accn_id and accn_payments.accn_id

My question is when I am summing the PAID_AMT and COPAY_AMT, I am getting double/triple/quadrouple the number that I should be getting.

Is there an obvious problem with my join condition?

select sum(p.paid_amt) as SumPaidAmount
    , sum(p.copay_amt) as SumCoPay
    , p.pmt_date
    , d.load_Date
    , p.ACCN_ID
from  accn_payments p
join 
(
    select distinct load_date, accn_id 
    from accn_demographics
) d
    on p.ACCN_ID=d.ACCN_ID
where p.POSTED='Y'
    and p.pmt_date between '20120701' and '20120731'
group by p.pmt_date, d.load_Date,p.ACCN_ID
order by 3 desc

thanks so much for your guidance.

Answer 1

You need to do the summation in a subquery:

select sum(p.SumPaidAmount) as SumPaidAmount, sum(p.SumCoPay) as SumCoPay,
       p.pmt_date, d.load_Date, p.ACCN_ID
from  (select accn_id, p.pmt_date, sum(paid_amt) as SumPaidAmt,
              sum(copay_amt) as SumCoPay
       from accn_payments p
       where p.POSTED='Y' and
             p.pmt_date between '20120701' and '20120731'
       group by accn_id, pmt_date
      ) p join
      (select distinct load_date, accn_id from accn_demographics) d
      on p.ACCN_ID=d.ACCN_ID
group by p.pmt_date, d.load_Date,p.ACCN_ID
order by 3 desc

Question: do you really intend for pmt_date to be in the final results? It looks like you want to remove it from both the outer SELECT and the subquery.