First DISTINCT and then Group by

Question

I have few records that have repeating values. I want to sum only the unique values. I am using Distinct clause to get Distinct records and doing group by to get the sum. But it seems like it is doing the sum and then returning the distinct values so my summed value comes out to be incorrect. Is there a way to only SUM the distinct records?

Answer 1

Could you please send us the query, because I tried something like that and it worked.
Wrote file afiedt.buf
1 select deptno, ename, sal from emp
2* WHERE deptno = '20'
3 /
DEPTNO ENAME SAL
20 SMITH 800
20 JONES 2975
20 SCOTT 3000
20 ADAMS 1100
20 FORD 3000
20 TEST100
6 rows selected.
SQL> select sum(DISTINCT sal) FROM emp WHERE deptno = '20';
SUM(DISTINCTSAL)
7875
SQL> ed
Wrote file afiedt.buf
1 select deptno,sum(DISTINCT sal) FROM emp WHERE deptno = '20'
2* GROUP by deptno
3 /
DEPTNO SUM(DISTINCTSAL)
20 7875
SQL> ed
Wrote file afiedt.buf
1 select deptno,sum(DISTINCT sal) FROM emp
2* GROUP by deptno
SQL> /
DEPTNO SUM(DISTINCTSAL)
10 9625
20 7875
30 13550
Thanks