create_tsparser.sgml

postgresql8.3.4源码,开源数据库

<!--
$PostgreSQL: pgsql/doc/src/sgml/ref/create_tsparser.sgml,v 1.1 2007/08/21 21:08:47 tgl Exp $
PostgreSQL documentation
-->

<refentry id="SQL-CREATETSPARSER">
 <refmeta>
  <refentrytitle id="sql-createtsparser-title">CREATE TEXT SEARCH PARSER</refentrytitle>
  <refmiscinfo>SQL - Language Statements</refmiscinfo>
 </refmeta>

 <refnamediv>
  <refname>CREATE TEXT SEARCH PARSER</refname>
  <refpurpose>define a new text search parser</refpurpose>
 </refnamediv>

 <indexterm zone="sql-createtsparser">
  <primary>CREATE TEXT SEARCH PARSER</primary>
 </indexterm>

 <refsynopsisdiv>
<synopsis>
CREATE TEXT SEARCH PARSER <replaceable class="parameter">name</replaceable> (
    START = <replaceable class="parameter">start_function</replaceable> ,
    GETTOKEN = <replaceable class="parameter">gettoken_function</replaceable> ,
    END = <replaceable class="parameter">end_function</replaceable> ,
    LEXTYPES = <replaceable class="parameter">lextypes_function</replaceable>
    [, HEADLINE = <replaceable class="parameter">headline_function</replaceable> ]
)
</synopsis>
 </refsynopsisdiv>

 <refsect1>
  <title>Description</title>

  <para>
   <command>CREATE TEXT SEARCH PARSER</command> creates a new text search
   parser.  A text search parser defines a method for splitting a text
   string into tokens and assigning types (categories) to the tokens.
   A parser is not particularly useful by itself, but must be bound into a
   text search configuration along with some text search dictionaries
   to be used for searching.
  </para>

  <para>
   If a schema name is given then the text search parser is created in the
   specified schema.  Otherwise it is created in the current schema.
  </para>

  <para>
   You must be a superuser to use <command>CREATE TEXT SEARCH PARSER</command>.
   (This restriction is made because an erroneous text search parser
   definition could confuse or even crash the server.)
  </para>

  <para>
   Refer to <xref linkend="textsearch"> for further information.
  </para>
 </refsect1>
  
 <refsect1>
  <title>Parameters</title>

  <variablelist>
   <varlistentry>
    <term><replaceable class="parameter">name</replaceable></term>
    <listitem>
     <para>
      The name of the text search parser to be created.  The name can be
      schema-qualified.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">start_function</replaceable></term>
    <listitem>
     <para>
      The name of the start function for the parser.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">gettoken_function</replaceable></term>
    <listitem>
     <para>
      The name of the get-next-token function for the parser.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">end_function</replaceable></term>
    <listitem>
     <para>
      The name of the end function for the parser.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">lextypes_function</replaceable></term>
    <listitem>
     <para>
      The name of the lextypes function for the parser (a function that
      returns information about the set of token types it produces).
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">headline_function</replaceable></term>
    <listitem>
     <para>
      The name of the headline function for the parser (a function that
      summarizes a set of tokens).
     </para>
    </listitem>
   </varlistentry>
  </variablelist>

  <para>
   The function names can be schema-qualified if necessary.  Argument types
   are not given, since the argument list for each type of function is
   predetermined.  All except the headline function are required.
  </para>

  <para>
   The arguments can appear in any order, not only the one shown above.
  </para>
 </refsect1>
 
 <refsect1>
  <title>Compatibility</title>

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

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

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