fun getRangeQueryR(k1: K, k2: K): List<NodeTransfer> (source)
Retrieve from the database all nodes n s.t. k1 ≤ n.k_min < k2 < n.k_max, ordered by ascending level.
k1 - the minimum key in the range.
k2 - the maximum key in the range.
Return
the list of retrieved nodes.