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As far as I understand the user could change the information for some nodes or add new nodes to the RadTreeView (both on client or server-side) and you want at some point to save the RadTreeView data in your data base. In order to achieve such functionality I would suggest using the RadTreeView GetAllNodes() server-side method that will retrieve all nodes recursively in the hierarchy. Once you have a collection that contains RadTreeView nodes object you can simply iterate through each of those objects and save the information in your data base.
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