How to display Opening Balance

Question

Hi

  I have below Data returned by query and i want to display Opening Balance.

I have following table named table1 with following data

Ac#     Date            Debit     Credit
1     1-Jan-15                    100
1     1-Jan-15                    100
1     2-Jan-15          200     
1     2-Jan-15          300     
1     3-Jan-15                    200
1     3-Jan-15                    100

Now User gives parameter date range as following Date >= 2-Jan-15 and Date<= 3-Jan-15 Now the data will be display in report as following

Ac#     Date            Debit     Credit
Op Bal                             200
1     2-Jan-15          200     
1     2-Jan-15          300     
1     3-Jan-15                    200
1     3-Jan-15                    100

Thanks