>>how these codes will work in sqL
>>

>>select accounts
>> 
>> Locate For code=thisform.code.value
>> opbl = opdr-opcr
>>  
>> sele student
>> Set Order To date
>> Set Filter To
>> Set Filter To code=thisform.code.value
>> 
>> Goto Top
>> Replace balance With 0 All
>> Goto Top
>> dfgblnc = opbl
>> Do While !Eof()
>>    dfgblnc = dfgblnc+debit-credit
>>     Replace balance With dfgblnc
>>     Skip
>> Enddo
>>

>
>
>
>

>myCode = thisform.code.value
>UPDATE Accounts;
>       SET Balance = opdr-opcr+debit-credit;
>WHERE Code == m.myCode
>

I may be wrong, but this code

dfgblnc = dfgblnc+debit-credit

seemed to me like incrementing on each record, while your code updates balance based on the current record values.

Though your code makes more sense.