code: private Scan projectFamilyDeletes(Scan scan) {
      for (Map.Entry<byte[], NavigableSet<byte[]>> entry : scan.getFamilyMap().entrySet()) {
        NavigableSet<byte[]> columns = entry.getValue();
        // wildcard scans will automatically include the delete marker, so only need to add it when we have
        // explicit columns listed
        if (columns != null && !columns.isEmpty()) {
          scan.addColumn(entry.getKey(), TxConstants.FAMILY_DELETE_QUALIFIER);
        }
      }
      return scan;
    }
docs: Ensures that family delete markers are present in the columns requested for any scan operation.
  @param scan The original scan request
  @return The modified scan request with the family delete qualifiers represented