ove, since there is no <code class="literal">ORDER BY</code> in the <code class="literal">OVER</code>
    clause, the window frame is the same as the partition, which for lack of
    <code class="literal">PARTITION BY</code> is the whole table; in other words each sum is
    taken over the whole table and so we get the same result for each output
    row.  But if we add an <code class="literal">ORDER BY</code> clause, we get very different
    results:
   </p><pre class="programlisting">
SELECT salary, sum(