Need urgent help with the query - Beginer

Question

Hello - I need help with a query to populate data in a table.Here is the scenario.
Source1
MnthID BranchCod CustID SegCode FXStatus ProfStatus Profit
200712 B1 C1 20 Y Y 100
Source2
MnthID BranchCod CustID ProdCode ProdIndex
200712 B1 C1 12 1
200712 B1 C2 12 0
Destination
MnthID BranchCod SegCode ProdCode CountSegCust CountProdCust ProfitProdCust
Condition and Calculations:
1)Source1 customer are base customers.If Source2 has customers who is not in source1 then that customer's record should not be fetched.
2)SegCode, FX Status, ProfStatus is one variable in destination table. [ SegCode = SegCode+ FXStatus (if FXStatus = Y)+ ProfStatus (if FXStatus = Y) ]
3)CountSegCust = CountCustID Groupby MnthID,BranchCod,SegCode Only.
4)CountProdCust = CountCustID Groupby MnthID,BranchCod,SegCode,ProdCode (when ProdIndex = 1)
5)ProfitProdCust = Sum of Profit of Customers Groupby MnthID,BranchCod,SegCode,ProdCode (when ProdIndex = 1)
Apologies for bad formatting.
Thanks in advance!!

Answer 1

A total guess indeed.
It's not clear whether some aggregation can be done (summing counts of grouped data might cause some customers being counted more than once)
insert into destination
select mnthid,branchcod,segcode,prodcode,countsegcust,countprodcust,profitprodcust
  from (select s1.mnthid,
               s1.branchcod,
               s1.segcode || case s1.fxstatus when 'Y' then s1.fxstatus || s1.profstatus end segcode,
               s2.prodcode,
               count(s1.custid) over (partition by s1.mnthid,
                                                   s1.branchcod,
                                                   s1.segcode || case s1.fxstatus when 'Y' then s1.fxstatus || s1.profstatus end
                                          order by null
                                     ) countsegcust,
               count(case proindex when 1
                                   then custid
                     end
                    ) over (partition by s1.mnthid,
                                         s1.branchcod,
                                         s1.segcode || case s1.fxstatus when 'Y' then s1.fxstatus || s1.profstatus end
                                         s2.prodcode
                                order by null
                           ) countprodcust,
               sum(case proindex when 1
                                 then profit
                   end
                  ) over (partition by s1.mnthid,
                                       s1.branchcod,
                                       s1.segcode || case s1.fxstatus when 'Y' then s1.fxstatus || s1.profstatus end
                                       s2.prodcode
                              order by null
                         ) profitprodcust,
               row_number() over (partition by s1.mnthid,
                                               s1.branchcod,
                                               s1.segcode || case s1.fxstatus when 'Y' then s1.fxstatus || s1.profstatus end
                                               s2.prodcode
                                      order by null
                                 ) the_row
          from source1 s1,source2 s2
         where s1.mnthid = s2.mnthid
           and s1.branchcod = s2.branchcod
           and s1.custid = s2.custid
where the_row = 1Regards
Etbin