begriffs open source - ai-pg/blob - full-docs/src/sgml/html/tutorial-views.html

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   3     Refer back to the queries in <a class="xref" href="tutorial-join.html" title="2.6. Joins Between Tables">Section 2.6</a>.
   4     Suppose the combined listing of weather records and city location
   5     is of particular interest to your application, but you do not want
   6     to type the query each time you need it.  You can create a
   7     <em class="firstterm">view</em> over the query, which gives a name to
   8     the query that you can refer to like an ordinary table:
   9
  10 </p><pre class="programlisting">
  11 CREATE VIEW myview AS
  12     SELECT name, temp_lo, temp_hi, prcp, date, location
  13         FROM weather, cities
  14         WHERE city = name;
  15
  16 SELECT * FROM myview;
  17 </pre><p>
  18    </p><p>
  19     Making liberal use of views is a key aspect of good SQL database
  20     design.  Views allow you to encapsulate the details of the
  21     structure of your tables, which might change as your application
  22     evolves, behind consistent interfaces.
  23    </p><p>
  24     Views can be used in almost any place a real table can be used.
  25     Building views upon other views is not uncommon.
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