Initially, I want to make a note that performing complex grid operations such as Inserting, Deleting, Updating, Hierarchy relations, Grouping, Exporting, Paging, Sorting, Filtering, etc. require accommodating appropriate database operations. Therefore, we suggest you to avoid Simple Databinding and strongly recommend the use of more advanced databinding methods, which automatically handle the aforementioned functions:
Advanced Data Binding
In that sense, you can either use a datasource control in your mark-up with SP or configure your SP programmatically making avail of the NeedDataSource event handler.
For your convenience, I'm sending a sample RadGrid web site to demonstrate a the suggested approach. Please check the logic in the attached application and let me know if it helps you.
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