includes/SearchMySQL.php

   1 <?php
   2 # Copyright (C) 2004 Brion Vibber <brion@pobox.com>
   3 # http://www.mediawiki.org/
   4 #
   5 # This program is free software; you can redistribute it and/or modify
   6 # it under the terms of the GNU General Public License as published by
   7 # the Free Software Foundation; either version 2 of the License, or
   8 # (at your option) any later version.
   9 #
  10 # This program is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13 # GNU General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU General Public License along
  16 # with this program; if not, write to the Free Software Foundation, Inc.,
  17 # 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18 # http://www.gnu.org/copyleft/gpl.html
  19
  20 /**
  21  * Search engine hook base class for MySQL.
  22  * Specific bits for MySQL 3 and 4 variants are in child classes.
  23  * @package MediaWiki
  24  * @subpackage Search
  25  */
  26
  27 /** */
  28 require_once( 'SearchEngine.php' );
  29
  30 class SearchMySQL extends SearchEngine {
  31         /**
  32          * Perform a full text search query and return a result set.
  33          *
  34          * @param string $term - Raw search term
  35          * @return MySQLSearchResultSet
  36          * @access public
  37          */
  38         function searchText( $term ) {
  39                 $resultSet = $this->db->resultObject( $this->db->query( $this->getQuery( $this->filter( $term ), true ) ) );
  40                 return new MySQLSearchResultSet( $resultSet, $this->searchTerms );
  41         }
  42
  43         /**
  44          * Perform a title-only search query and return a result set.
  45          *
  46          * @param string $term - Raw search term
  47          * @return MySQLSearchResultSet
  48          * @access public
  49          */
  50         function searchTitle( $term ) {
  51                 $resultSet = $this->db->resultObject( $this->db->query( $this->getQuery( $this->filter( $term ), false ) ) );
  52                 return new MySQLSearchResultSet( $resultSet, $this->searchTerms );
  53         }
  54
  55
  56         /**
  57          * Return a partial WHERE clause to exclude redirects, if so set
  58          * @return string
  59          * @access private
  60          */
  61         function queryRedirect() {
  62                 if( $this->showRedirects ) {
  63                         return 'AND cur_is_redirect=0';
  64                 } else {
  65                         return '';
  66                 }
  67         }
  68
  69         /**
  70          * Return a partial WHERE clause to limit the search to the given namespaces
  71          * @return string
  72          * @access private
  73          */
  74         function queryNamespaces() {
  75                 $namespaces = implode( ',', $this->namespaces );
  76                 if ($namespaces == '') {
  77                         $namespaces = '0';
  78                 }
  79                 return 'AND page_namespace IN (' . $namespaces . ')';
  80         }
  81
  82         /**
  83          * Return a LIMIT clause to limit results on the query.
  84          * @return string
  85          * @access private
  86          */
  87         function queryLimit() {
  88                 return $this->db->limitResult( $this->limit, $this->offset );
  89         }
  90
  91         /**
  92          * Does not do anything for generic search engine
  93          * subclasses may define this though
  94          * @return string
  95          * @access private
  96          */
  97         function queryRanking( $filteredTerm, $fulltext ) {
  98                 return "";
  99         }
 100
 101         /**
 102          * Construct the full SQL query to do the search.
 103          * The guts shoulds be constructed in queryMain()
 104          * @param string $filteredTerm
 105          * @param bool $fulltext
 106          * @access private
 107          */
 108         function getQuery( $filteredTerm, $fulltext ) {
 109                 return $this->queryMain( $filteredTerm, $fulltext ) . ' ' .
 110                         $this->queryRedirect() . ' ' .
 111                         $this->queryNamespaces() . ' ' .
 112                         $this->queryRanking( $filteredTerm, $fulltext ) . ' ' .
 113                         $this->queryLimit();
 114         }
 115
 116
 117         /**
 118          * Picks which field to index on, depending on what type of query.
 119          * @param bool $fulltext
 120          * @return string
 121          */
 122         function getIndexField( $fulltext ) {
 123                 return $fulltext ? 'si_text' : 'si_title';
 124         }
 125
 126         /**
 127          * Get the base part of the search query.
 128          * The actual match syntax will depend on the server
 129          * version; MySQL 3 and MySQL 4 have different capabilities
 130          * in their fulltext search indexes.
 131          *
 132          * @param string $filteredTerm
 133          * @param bool $fulltext
 134          * @return string
 135          * @access private
 136          */
 137         function queryMain( $filteredTerm, $fulltext ) {
 138                 $match = $this->parseQuery( $filteredTerm, $fulltext );
 139                 $page        = $this->db->tableName( 'page' );
 140                 $searchindex = $this->db->tableName( 'searchindex' );
 141                 return 'SELECT page_id, page_namespace, page_title ' .
 142                         "FROM $page,$searchindex " .
 143                         'WHERE page_id=si_page AND ' . $match;
 144         }
 145
 146         /**
 147          * Create or update the search index record for the given page.
 148          * Title and text should be pre-processed.
 149          *
 150          * @param int $id
 151          * @param string $title
 152          * @param string $text
 153          */
 154         function update( $id, $title, $text ) {
 155                 $dbw=& wfGetDB( DB_MASTER );
 156                 $dbw->replace( 'searchindex',
 157                         array( 'si_page' ),
 158                         array(
 159                                 'si_page' => $id,
 160                                 'si_title' => $title,
 161                                 'si_text' => $text
 162                         ), 'SearchMySQL4::update' );
 163         }
 164
 165         /**
 166          * Update a search index record's title only.
 167          * Title should be pre-processed.
 168          *
 169          * @param int $id
 170          * @param string $title
 171          */
 172     function updateTitle( $id, $title ) {
 173                 $dbw =& wfGetDB( DB_MASTER );
 174
 175                 $dbw->update( array( 'searchindex' ),
 176                         array( 'si_title' => $title ),
 177                         array( 'si_page'  => $id ),
 178                         'SearchMySQL4::updateTitle',
 179                         $dbw->lowPriorityOption() );
 180         }
 181 }
 182
 183 class MySQLSearchResultSet extends SearchResultSet {
 184         function MySQLSearchResultSet( $resultSet, $terms ) {
 185                 $this->mResultSet = $resultSet;
 186                 $this->mTerms = $terms;
 187         }
 188
 189         function termMatches() {
 190                 return $this->mTerms;
 191         }
 192
 193         function numRows() {
 194                 return $this->mResultSet->numRows();
 195         }
 196
 197         function next() {
 198                 $row = $this->mResultSet->fetchObject();
 199                 if( $row === false ) {
 200                         return false;
 201                 } else {
 202                         return new SearchResult( $row );
 203                 }
 204         }
 205 }
 206
 207 ?>