You can deselect a selected item in RadComboBox by setting the SelectedIndex property to -1 and clearing the SelectedItems collection if there are multiple selected items.
If this does not help, please explain in more detail what your goal is since I could not fully understand it from the information provided. RadComboBox serves simply as a visualization of data, but it knows nothing about databases, constraints, relations or data tables. Thanks.
I am looking forward to your reply.
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