dataadapter update question

Hi all

Im a new .net user and my problem is with ADO.NET.
I have a dataset populated with two tables. The tables have a parent-child relationship which I created using datarelations. Now I update values for certain fields in both tables based on a result set derived using the primary key. ( ie. equivalent to "select table1.a, table2.b from table1, table2 where table1.c = table2.c." this is how I would get the result set in vb6. In VB.NET, I used the datarowview to iterate through the resultset) My problem is when i call the dataadapter update method, the changes made in the dataset to the two ralated tables have to propogate to their respective tables in the datasource. Could someone pls tell me how am i to accomplish this?

thanx in advance.

Al