  actual indexes.
  </p></div><div class="sect2" id="RANGETYPES-CONSTRAINT"><div class="titlepage"><div><div><h3 class="title">8.17.10. Constraints on Ranges <a href="#RANGETYPES-CONSTRAINT" class="id_link">#</a></h3></div></div></div><a id="id-1.5.7.25.16.2" class="indexterm"></a><p>
   While <code class="literal">UNIQUE</code> is a natural constraint for scalar
   values, it is usually unsuitable for range types. Instead, an
   exclusion constraint is often more appropriate
   (see <a class="link" href="