RocksDB provides an API DB::GetSnapshot() to get a snapshot. A snapshot is actually an LSN, all keys with LSN less or equal than this LSN is visible, while all keys with LSN greater than this LSN is not visible.
I wonder if there are some ways that we can diff two snapshot? For example, given LSN1 and LSN2(LSN1 < LSN2), is it possible that we can iterate all keys that has LSN greater than LSN1 and less than LSN2.