diff --git a/doc/src/sgml/datatype.sgml b/doc/src/sgml/datatype.sgml
new file mode 100644
index bc1ec3f..ab8eb2d
*** a/doc/src/sgml/datatype.sgml
--- b/doc/src/sgml/datatype.sgml
*************** P <optional> <replaceable>years</>-<repl
*** 2784,2792 ****
      <productname>PostgreSQL</productname> provides the
      standard <acronym>SQL</acronym> type <type>boolean</type>;
      see <xref linkend="datatype-boolean-table">.
!     The <type>boolean</type> type can have one of only two states:
!     <quote>true</quote> or <quote>false</quote>.  A third state,
!     <quote>unknown</quote>, is represented by the
      <acronym>SQL</acronym> null value.
     </para>
  
--- 2784,2792 ----
      <productname>PostgreSQL</productname> provides the
      standard <acronym>SQL</acronym> type <type>boolean</type>;
      see <xref linkend="datatype-boolean-table">.
!     The <type>boolean</type> type can have several states:
!     <quote>true</quote>, <quote>false</quote>, and a third state,
!     <quote>unknown</quote>, which is represented by the
      <acronym>SQL</acronym> null value.
     </para>