1- <!-- $PostgreSQL: pgsql/doc/src/sgml/datatype.sgml,v 1.251 2010/07/16 02:15:53 tgl Exp $ -->
1+ <!-- $PostgreSQL: pgsql/doc/src/sgml/datatype.sgml,v 1.252 2010/07/24 12:17:35 petere Exp $ -->
22
33 <chapter id="datatype">
44 <title>Data Types</title>
@@ -2759,13 +2759,34 @@ P <optional> <replaceable>years</>-<replaceable>months</>-<replaceable>days</> <
27592759
27602760 <para>
27612761 <productname>PostgreSQL</productname> provides the
2762- standard <acronym>SQL</acronym> type <type>boolean</type>.
2763- <type>boolean</type> can have one of only two states:
2762+ standard <acronym>SQL</acronym> type <type>boolean</type>;
2763+ see <xref linkend="datatype-boolean-table">.
2764+ The <type>boolean</type> type can have one of only two states:
27642765 <quote>true</quote> or <quote>false</quote>. A third state,
27652766 <quote>unknown</quote>, is represented by the
27662767 <acronym>SQL</acronym> null value.
27672768 </para>
27682769
2770+ <table id="datatype-boolean-table">
2771+ <title>Boolean Data Type</title>
2772+ <tgroup cols="3">
2773+ <thead>
2774+ <row>
2775+ <entry>Name</entry>
2776+ <entry>Storage Size</entry>
2777+ <entry>Description</entry>
2778+ </row>
2779+ </thead>
2780+ <tbody>
2781+ <row>
2782+ <entry><type>boolean</type></entry>
2783+ <entry>1 byte</entry>
2784+ <entry>state of true of false</entry>
2785+ </row>
2786+ </tbody>
2787+ </tgroup>
2788+ </table>
2789+
27692790 <para>
27702791 Valid literal values for the <quote>true</quote> state are:
27712792 <simplelist>
@@ -2794,6 +2815,12 @@ P <optional> <replaceable>years</>-<replaceable>months</>-<replaceable>days</> <
27942815 (<acronym>SQL</acronym>-compliant) usage.
27952816 </para>
27962817
2818+ <para>
2819+ <xref linkend="datatype-boolean-example"> shows that
2820+ <type>boolean</type> values are output using the letters
2821+ <literal>t</literal> and <literal>f</literal>.
2822+ </para>
2823+
27972824 <example id="datatype-boolean-example">
27982825 <title>Using the <type>boolean</type> type</title>
27992826
@@ -2813,16 +2840,6 @@ SELECT * FROM test1 WHERE a;
28132840 t | sic est
28142841</programlisting>
28152842 </example>
2816-
2817- <para>
2818- <xref linkend="datatype-boolean-example"> shows that
2819- <type>boolean</type> values are output using the letters
2820- <literal>t</literal> and <literal>f</literal>.
2821- </para>
2822-
2823- <para>
2824- <type>boolean</type> uses 1 byte of storage.
2825- </para>
28262843 </sect1>
28272844
28282845 <sect1 id="datatype-enum">