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<title>3.2.Views</title>
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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="tutorial-views"></a>3.2.Views</h2></div></div></div>
<a name="id569690"></a><p> Refer back to the queries in <a href="tutorial-join.html" title="2.6.Joins Between Tables">Section2.6, “Joins Between Tables”</a>.
Suppose the combined listing of weather records and city location
is of particular interest to your application, but you do not want
to type the query each time you need it. You can create a
<em class="firstterm">view</em> over the query, which gives a name to
the query that you can refer to like an ordinary table.
</p>
<pre class="programlisting">CREATE VIEW myview AS
SELECT city, temp_lo, temp_hi, prcp, date, location
FROM weather, cities
WHERE city = name;
SELECT * FROM myview;</pre>
<p>
</p>
<p> Making liberal use of views is a key aspect of good SQL database
design. Views allow you to encapsulate the details of the
structure of your tables, which may change as your application
evolves, behind consistent interfaces.
</p>
<p> Views can be used in almost any place a real table can be used.
Building views upon other views is not uncommon.
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