How to insert one table attributes value to another table.

[Moss ali]

I have 3 tables in my Db Supplier with started Supplier-id=C001 up to C999,Each supplier have many Contacts.On some condition i want to assign one table values to second table only those values which are related to that condition let suppose Supplier S010 marge his Business With Supplier S090 then S010 Contacts table values are assigned to S090 Contacts.Can I fetch record from table store in Dataset then assign to other table.Pls help me out what is the best approch.Keep in mind that Supplier-id code is hard coded value i calculate max() then increment with one.Tnx in advance.ASP.NET 3.5 SQL2005 C#