Oracle Rolling or Running totals by month

Question

Goal: Rolling/Running total for all statements at the end of each month.

Code:

select 
    TRUNC(ACTHX.STMT_HX_STMT_DATE, \'MM\') AS MNTH, 
    COUNT(ACT         


        

Answer 1

An alternative solution that provides the same rolling totals without the sub query.

SELECT
        DISTINCT TRUNC(ACTHX.STMT_HX_STMT_DATE,'MM') AS MNTH
        ,count(ACTHX.INVOICE) OVER (ORDER BY TRUNC(ACTHX.STMT_HX_STMT_DATE,'MM')) AS STMTS
    FROM  ACTHX
    ORDER BY
        TRUNC(ACTHX.STMT_HX_STMT_DATE,'MM')

Answer 2

It sounds like you want the running total. You can use the analytic SUM function for that.

select mnth,
       sum(stmts) over (order by mnth) stmts
  from (select TRUNC(ACTHX.STMT_HX_STMT_DATE, 'MM') AS MNTH, 
               COUNT(ACTHX.INVOICE) as STMTS
          from ACTHX
         group by TRUNC(ACTHX.STMT_HX_STMT_DATE, 'MM'))
 ORDER BY mnth