doc/src/sgml/ref/create_tsparser.sgml

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   2 $PostgreSQL$
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   5
   6 <refentry id="SQL-CREATETSPARSER">
   7  <refmeta>
   8   <refentrytitle id="sql-createtsparser-title">CREATE TEXT SEARCH PARSER</refentrytitle>
   9   <refmiscinfo>SQL - Language Statements</refmiscinfo>
  10  </refmeta>
  11
  12  <refnamediv>
  13   <refname>CREATE TEXT SEARCH PARSER</refname>
  14   <refpurpose>define a new text search parser</refpurpose>
  15  </refnamediv>
  16
  17  <indexterm zone="sql-createtsparser">
  18   <primary>CREATE TEXT SEARCH PARSER</primary>
  19  </indexterm>
  20
  21  <refsynopsisdiv>
  22 <synopsis>
  23 CREATE TEXT SEARCH PARSER <replaceable class="parameter">name</replaceable> (
  24     START = <replaceable class="parameter">start_function</replaceable> ,
  25     GETTOKEN = <replaceable class="parameter">gettoken_function</replaceable> ,
  26     END = <replaceable class="parameter">end_function</replaceable> ,
  27     LEXTYPES = <replaceable class="parameter">lextypes_function</replaceable>
  28     [, HEADLINE = <replaceable class="parameter">headline_function</replaceable> ]
  29 )
  30 </synopsis>
  31  </refsynopsisdiv>
  32
  33  <refsect1>
  34   <title>Description</title>
  35
  36   <para>
  37    <command>CREATE TEXT SEARCH PARSER</command> creates a new text search
  38    parser.  A text search parser defines a method for splitting a text
  39    string into tokens and assigning types (categories) to the tokens.
  40    A parser is not particularly useful by itself, but must be bound into a
  41    text search configuration along with some text search dictionaries
  42    to be used for searching.
  43   </para>
  44
  45   <para>
  46    If a schema name is given then the text search parser is created in the
  47    specified schema.  Otherwise it is created in the current schema.
  48   </para>
  49
  50   <para>
  51    You must be a superuser to use <command>CREATE TEXT SEARCH PARSER</command>.
  52    (This restriction is made because an erroneous text search parser
  53    definition could confuse or even crash the server.)
  54   </para>
  55
  56   <para>
  57    Refer to <xref linkend="textsearch"> for further information.
  58   </para>
  59  </refsect1>
  60
  61  <refsect1>
  62   <title>Parameters</title>
  63
  64   <variablelist>
  65    <varlistentry>
  66     <term><replaceable class="parameter">name</replaceable></term>
  67     <listitem>
  68      <para>
  69       The name of the text search parser to be created.  The name can be
  70       schema-qualified.
  71      </para>
  72     </listitem>
  73    </varlistentry>
  74
  75    <varlistentry>
  76     <term><replaceable class="parameter">start_function</replaceable></term>
  77     <listitem>
  78      <para>
  79       The name of the start function for the parser.
  80      </para>
  81     </listitem>
  82    </varlistentry>
  83
  84    <varlistentry>
  85     <term><replaceable class="parameter">gettoken_function</replaceable></term>
  86     <listitem>
  87      <para>
  88       The name of the get-next-token function for the parser.
  89      </para>
  90     </listitem>
  91    </varlistentry>
  92
  93    <varlistentry>
  94     <term><replaceable class="parameter">end_function</replaceable></term>
  95     <listitem>
  96      <para>
  97       The name of the end function for the parser.
  98      </para>
  99     </listitem>
 100    </varlistentry>
 101
 102    <varlistentry>
 103     <term><replaceable class="parameter">lextypes_function</replaceable></term>
 104     <listitem>
 105      <para>
 106       The name of the lextypes function for the parser (a function that
 107       returns information about the set of token types it produces).
 108      </para>
 109     </listitem>
 110    </varlistentry>
 111
 112    <varlistentry>
 113     <term><replaceable class="parameter">headline_function</replaceable></term>
 114     <listitem>
 115      <para>
 116       The name of the headline function for the parser (a function that
 117       summarizes a set of tokens).
 118      </para>
 119     </listitem>
 120    </varlistentry>
 121   </variablelist>
 122
 123   <para>
 124    The function names can be schema-qualified if necessary.  Argument types
 125    are not given, since the argument list for each type of function is
 126    predetermined.  All except the headline function are required.
 127   </para>
 128
 129   <para>
 130    The arguments can appear in any order, not only the one shown above.
 131   </para>
 132  </refsect1>
 133
 134  <refsect1>
 135   <title>Compatibility</title>
 136
 137   <para>
 138    There is no
 139    <command>CREATE TEXT SEARCH PARSER</command> statement in the SQL
 140    standard.
 141   </para>
 142  </refsect1>
 143
 144  <refsect1>
 145   <title>See Also</title>
 146
 147   <simplelist type="inline">
 148    <member><xref linkend="sql-altertsparser" endterm="sql-altertsparser-title"></member>
 149    <member><xref linkend="sql-droptsparser" endterm="sql-droptsparser-title"></member>
 150   </simplelist>
 151  </refsect1>
 152 </refentry>