e records
        based on a single characteristic. You can, for example, find all the
        automobiles that are red. Or you can find all the automobiles that have
        four doors. Or all the automobiles that are minivans. 
    </p>
      <p>
        The next most natural step, then, is to form compound queries, or joins.
        For example, you might want to find all the automobiles that are red,
        and that were built by Toyota, and that are minivans. You can do this
        using a 
         