code: private void upgradeTable(TableEntry10 table, 
                              TableUpgrade upgradeTable)
      throws IOException
    {
      _pageMap = new TreeMap<>();
      
      readTableIndex(table);
      
      for (Page10 page : _pageMap.values()) {
        upgradeLeaf(table, upgradeTable, page);
        
        List<Delta10> deltas = page.deltas();
        
        if (deltas != null) {
          for (Delta10 delta : deltas) {
            upgradeDelta(table, upgradeTable, page, delta);
          }
        }
      }
    }
docs: Upgrade rows from a table.