RadTreeView does not support the automatic creation of tree-like structures by simply binding it to hierarchyid data. In order to use such data you'll need to create the hierarchical data structure that is described in the hierarchyid data. So, after you prepare your data structure you can bind the treeview to it. I am attaching a sample project demonstrating how to bind RadTreeView to a WCF web service - you can use it as a basis and modify it to fetch the data from your database and construct the data structure.
Greetings,
Tihomir Petkov
the Telerik team
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