Hi @rpaidar     Most, of the code that does this can be found in the "tablet" module.   Iterators for all rowsets are assembled in Tablet::CaptureConsistentIterators() (https://github.com/cloudera/kudu/blob/master/src/kudu/tablet/tablet.cc#L1572)   Then, for diskrowsets, the base data iterator is wrapped in a delta iterator. This process starts at DiskRowSet::NewRowIterator() (https://github.com/cloudera/kudu/blob/master/src/kudu/tablet/diskrowset.cc#L592)   To get more insight on how the base is materialized and deltas are applied you can follow the different iterators that are created in DiskRowSet::NewRowIterator().   HTH David        ... View more