<!--
$PostgreSQL: pgsql/doc/src/sgml/ref/alter_tsdictionary.sgml,v 1.3 2007/10/17 01:01:28 tgl Exp $
PostgreSQL documentation
-->

<refentry id="SQL-ALTERTSDICTIONARY">
 <refmeta>
  <refentrytitle id="SQL-ALTERTSDICTIONARY-TITLE">ALTER TEXT SEARCH DICTIONARY</refentrytitle>
  <refmiscinfo>SQL - Language Statements</refmiscinfo>
 </refmeta>

 <refnamediv>
  <refname>ALTER TEXT SEARCH DICTIONARY</refname>
  <refpurpose>change the definition of a text search dictionary</refpurpose>
 </refnamediv>  
  
 <indexterm zone="sql-altertsdictionary">
  <primary>ALTER TEXT SEARCH DICTIONARY</primary>
 </indexterm>

 <refsynopsisdiv>
<synopsis>
ALTER TEXT SEARCH DICTIONARY <replaceable>name</replaceable> (
    <replaceable class="parameter">option</replaceable> [ = <replaceable class="parameter">value</replaceable> ] [, ... ]
)
ALTER TEXT SEARCH DICTIONARY <replaceable>name</replaceable> RENAME TO <replaceable>newname</replaceable>
ALTER TEXT SEARCH DICTIONARY <replaceable>name</replaceable> OWNER TO <replaceable>newowner</replaceable>
</synopsis>
 </refsynopsisdiv>
  
 <refsect1>
  <title>Description</title>

  <para>
   <command>ALTER TEXT SEARCH DICTIONARY</command> changes the definition of
   a text search dictionary.  You can change the dictionary's
   template-specific options, or change the dictionary's name or owner.
  </para>

  <para>
   You must be the owner of the dictionary to use
   <command>ALTER TEXT SEARCH DICTIONARY</>.
  </para>
 </refsect1>
  
 <refsect1>
  <title>Parameters</title>

  <variablelist>
   <varlistentry>
    <term><replaceable class="parameter">name</replaceable></term>
    <listitem>
     <para>
      The name (optionally schema-qualified) of an existing text search
      dictionary.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">option</replaceable></term>
    <listitem>
     <para>
      The name of a template-specific option to be set for this dictionary.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">value</replaceable></term>
    <listitem>
     <para>
      The new value to use for a template-specific option.
      If the equal sign and value are omitted, then any previous
      setting for the option is removed from the dictionary,
      allowing the default to be used.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">newname</replaceable></term>
    <listitem>
     <para>
      The new name of the text search dictionary.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">newowner</replaceable></term>
    <listitem>
     <para>
      The new owner of the text search dictionary.
     </para>
    </listitem>
   </varlistentry>
 </variablelist>

  <para>
   Template-specific options can appear in any order.
  </para>
 </refsect1>
  
 <refsect1>
  <title>Examples</title>

  <para>
   The following example command changes the stopword list
   for a Snowball-based dictionary.  Other parameters remain unchanged.
  </para>

<programlisting>
ALTER TEXT SEARCH DICTIONARY my_dict ( StopWords = newrussian );
</programlisting>  

  <para>
   The following example command changes the language option to dutch,
   and removes the stopword option entirely.
  </para>

<programlisting>
ALTER TEXT SEARCH DICTIONARY my_dict ( language = dutch, StopWords );
</programlisting>  

  <para>
   The following example command <quote>updates</> the dictionary's
   definition without actually changing anything.

<programlisting>
ALTER TEXT SEARCH DICTIONARY my_dict ( dummy );
</programlisting>

   (The reason this works is that the option removal code doesn't complain
   if there is no such option.)  This trick is useful when changing
   configuration files for the dictionary: the <command>ALTER</> will
   force existing database sessions to re-read the configuration files,
   which otherwise they would never do if they had read them earlier.
  </para>
 </refsect1>

 <refsect1>
  <title>Compatibility</title>

  <para>
   There is no <command>ALTER TEXT SEARCH DICTIONARY</command> statement in
   the SQL standard.
  </para>
 </refsect1>

 <refsect1>
  <title>See Also</title>

  <simplelist type="inline">
   <member><xref linkend="sql-createtsdictionary" endterm="sql-createtsdictionary-title"></member>
   <member><xref linkend="sql-droptsdictionary" endterm="sql-droptsdictionary-title"></member>
  </simplelist>
 </refsect1>
</refentry>
