Update/correct inheritance examples.
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<!--
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/Attic/inherit.sgml,v 1.18 2002/01/07 02:29:12 petere Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/Attic/inherit.sgml,v 1.19 2002/04/13 17:17:29 tgl Exp $
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-->
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-->
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<chapter id="inherit">
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<chapter id="inherit">
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@ -56,35 +56,28 @@ SELECT name, altitude
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which returns:
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which returns:
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<programlisting>
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<programlisting>
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+----------+----------+
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name | altitude
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|name | altitude |
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-----------+----------
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+----------+----------+
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Las Vegas | 2174
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|Las Vegas | 2174 |
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Mariposa | 1953
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+----------+----------+
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Madison | 845
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|Mariposa | 1953 |
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+----------+----------+
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|Madison | 845 |
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+----------+----------+
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</programlisting>
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</programlisting>
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</para>
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</para>
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<para>
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<para>
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On the other hand, the following query finds
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On the other hand, the following query finds
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all the cities that are not state capitals and
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all the cities that are not state capitals and
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are situated at an altitude of 500ft or higher:
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are situated at an altitude over 500ft:
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<programlisting>
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<programlisting>
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SELECT name, altitude
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SELECT name, altitude
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FROM ONLY cities
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FROM ONLY cities
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WHERE altitude > 500;
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WHERE altitude > 500;
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+----------+----------+
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name | altitude
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|name | altitude |
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-----------+----------
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+----------+----------+
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Las Vegas | 2174
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|Las Vegas | 2174 |
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Mariposa | 1953
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+----------+----------+
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|Mariposa | 1953 |
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+----------+----------+
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</programlisting>
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</programlisting>
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</para>
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</para>
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@ -112,18 +105,16 @@ SELECT name, altitude
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which returns:
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which returns:
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<programlisting>
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<programlisting>
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+---------+----------+----------+
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tableoid | name | altitude
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|tableoid |name | altitude |
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----------+-----------+----------
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+---------+----------+----------+
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139793 | Las Vegas | 2174
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|37292 |Las Vegas | 2174 |
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139793 | Mariposa | 1953
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+---------+----------+----------+
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139798 | Madison | 845
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|37280 |Mariposa | 1953 |
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+---------+----------+----------+
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|37280 |Madison | 845 |
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+---------+----------+----------+
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</programlisting>
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</programlisting>
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If you do a join with pg_class you can see the actual table name:
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(If you try to reproduce this example, you will probably get different
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numeric OIDs.) By doing a join with pg_class you can see the actual table
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names:
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<programlisting>
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<programlisting>
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SELECT p.relname, c.name, c.altitude
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SELECT p.relname, c.name, c.altitude
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@ -134,15 +125,11 @@ SELECT name, altitude
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which returns:
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which returns:
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<programlisting>
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<programlisting>
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+---------+----------+----------+
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relname | name | altitude
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|relname |name | altitude |
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----------+-----------+----------
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+---------+----------+----------+
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cities | Las Vegas | 2174
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|capitals |Las Vegas | 2174 |
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cities | Mariposa | 1953
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+---------+----------+----------+
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capitals | Madison | 845
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|cities |Mariposa | 1953 |
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+---------+----------+----------+
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|cities |Madison | 845 |
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+---------+----------+----------+
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</programlisting>
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</programlisting>
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</para>
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</para>
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