Kevin,

<--
Wouldn't the child records already have the parent code at the point where you save the DataSet?
>

Yes, but what is exactly the order of update? If its: the first record updated gets first to the database, then the child record will get there first and we will get an error. Since at this point, the parent does not yet exist, bits its already referenced by the child record.

No. Here's the scenario:
1- Create new record (1). parent code is null.
2- Create new record (2). parent code is null.
3- Modify record (1) and set parent code = (2).

Now, how do we handle such cases during batch update?

Thanks