Question

I’m performing a calulation that results in a floating point number. When I try and write it to a Access field, I get this error:

Run-time error '3759': Scaling of decimal value resulted in data truncation

I’ve intentionally limited the access field to a fixed precision. I was hoping that the value would be automatically truncated, but instead it’s throwing this error – how can I explicitly change the precision of the value in VBA to avoid this error?

Code:

value = X / Y
With myTAble
    .AddNew
    !calc = value
    .Update
End With

Answer 1

You could try using VBA’s Round function, as in:

!calc = Round(value, 2)

Replace the 2 with however many decimal places you want.

Depending on the scale and precision of your numbers, you might still encounter the 3759 error if Round returns a value that cannot be expressed exactly as a Double floating point number (and so ends up having more decimal places than you asked for). A more robust approach might be to use something like:

!calc = CDec(FormatNumber(value, 2))

Replace the 2 with however many decimal places you want.

FormatNumber will round the number and convert it to a string (with only the number of decimal places that you specify), and CDec will convert the string into a Decimal.