I am making a small utility in our program that returns a list of links where either the start node or end node (based on GUID) is not on the map along with a list of nodes that have that same or very close latitude and longitude as the missing points. I want to allow the user to then assign a selected node as the missing point to the link. This would entail updating the To_Node_Guid or From_Node_Guid on the link layer. How do I change the map data from within the code? I have not been able to find any examples of this. I have tried updating the cursor, but the changes do not persist.