code: @Override
      public int join(final OneSelect _oneSelect,
                      final SQLSelect _select,
                      final int _relIndex)
      {
          Integer ret;
          final String tableName = this.table.getSqlTable();
          ret = _oneSelect.getTableIndex(tableName, "ID", _relIndex, null);
          if (ret == null) {
              ret = _oneSelect.getNewTableIndex(tableName, "ID", _relIndex, null);
              _select.leftJoin(tableName, ret, "ID", _relIndex, "ID");
          }
          return ret;
      }
docs: {@inheritDoc}