A filtered copy of the DataTable that can have actions performed on it, and later be merged back in the DataTable using Merge. If no rows of the desired DataRowState are found, the method returns null.
The GetChanges method is used to produce a second DataTable object that contains only the changes introduced into the original. Use the rowStates argument to specify the type of changes the new object should include.
Relationship constraints may cause unchanged parent rows to be included.