How to find the cumulative Sum

Question

How to get the fastest result in 180 million records table to get the BTN(BillingTelephoneNbr) wise MonthlySalesCost.
select B.BTN,b.cost,sum(a.cost) as cum_sal
from Monthly_BTN a,Monthly_BTN b
where a.rowid <= b.rowid
group by b.rowid,b.BTN,b.cost.
Above query is taking up the too much time.
Option:-
a) partition the table
b) rebuild the index
c) alter the index
d) any other suggestion??
Let me know the best way.

Answer 1

I don't understand why you need a self-join.
See the following example, with cumulative sum about deptno :
SCOTT@demo102> ed
Wrote file afiedt.buf
  1  select empno, deptno, sal, sum(sal) over (partition by deptno order by empno)
  2  from emp
  3* order by deptno , empno
SCOTT@demo102> /
     EMPNO     DEPTNO        SAL SUM(SAL)OVER(PARTITIONBYDEPTNOORDERBYEMPNO)
      7782         10      24500                                       24500
      7839         10      50000                                       74500
      7934         10      13000                                       87500
      7369         20       8000                                        8000
      7566         20      29750                                       37750
      7788         20      30000                                       67750
      7876         20      11000                                       78750
      7902         20      30000                                      108750
      7499         30      16000                                       16000
      7521         30      12500                                       28500
      7654         30      12500                                       41000
      7698         30      28500                                       69500
      7844         30      15000                                       84500
      7900         30       9500                                       94000
14 rows selected.
SCOTT@demo102> So, your query would be :
select BTN,cost,sum(cost) over (partition by BTN order by BTN,cost) as ***_sal
from Monthly_BTN
order by BTN,cost;Anyway, a query without where clause on a huge table (180 million records) seems to me like a little strange, are you sure that you will read all rows ?
Nicolas.
partition or not partition about BTN... like you want.
Message was edited by:
N. Gasparotto