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 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 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 /** @package MediaWiki */
  28 class SearchMySQL extends SearchEngine {
  29         /**
  30          * Perform a full text search query and return a result set.
  31          *
  32          * @param string $term - Raw search term
  33          * @return MySQLSearchResultSet
  34          * @access public
  35          */
  36         function searchText( $term ) {
  37                 $resultSet = $this->db->resultObject( $this->db->query( $this->getQuery( $this->filter( $term ), true ) ) );
  38                 return new MySQLSearchResultSet( $resultSet, $this->searchTerms );
  39         }
  40
  41         /**
  42          * Perform a title-only search query and return a result set.
  43          *
  44          * @param string $term - Raw search term
  45          * @return MySQLSearchResultSet
  46          * @access public
  47          */
  48         function searchTitle( $term ) {
  49                 $resultSet = $this->db->resultObject( $this->db->query( $this->getQuery( $this->filter( $term ), false ) ) );
  50                 return new MySQLSearchResultSet( $resultSet, $this->searchTerms );
  51         }
  52
  53
  54         /**
  55          * Return a partial WHERE clause to exclude redirects, if so set
  56          * @return string
  57          * @private
  58          */
  59         function queryRedirect() {
  60                 if( $this->showRedirects ) {
  61                         return '';
  62                 } else {
  63                         return 'AND page_is_redirect=0';
  64                 }
  65         }
  66
  67         /**
  68          * Return a partial WHERE clause to limit the search to the given namespaces
  69          * @return string
  70          * @private
  71          */
  72         function queryNamespaces() {
  73                 $namespaces = implode( ',', $this->namespaces );
  74                 if ($namespaces == '') {
  75                         $namespaces = '0';
  76                 }
  77                 return 'AND page_namespace IN (' . $namespaces . ')';
  78         }
  79
  80         /**
  81          * Return a LIMIT clause to limit results on the query.
  82          * @return string
  83          * @private
  84          */
  85         function queryLimit() {
  86                 return $this->db->limitResult( '', $this->limit, $this->offset );
  87         }
  88
  89         /**
  90          * Does not do anything for generic search engine
  91          * subclasses may define this though
  92          * @return string
  93          * @private
  94          */
  95         function queryRanking( $filteredTerm, $fulltext ) {
  96                 return '';
  97         }
  98
  99         /**
 100          * Construct the full SQL query to do the search.
 101          * The guts shoulds be constructed in queryMain()
 102          * @param string $filteredTerm
 103          * @param bool $fulltext
 104          * @private
 105          */
 106         function getQuery( $filteredTerm, $fulltext ) {
 107                 return $this->queryMain( $filteredTerm, $fulltext ) . ' ' .
 108                         $this->queryRedirect() . ' ' .
 109                         $this->queryNamespaces() . ' ' .
 110                         $this->queryRanking( $filteredTerm, $fulltext ) . ' ' .
 111                         $this->queryLimit();
 112         }
 113
 114
 115         /**
 116          * Picks which field to index on, depending on what type of query.
 117          * @param bool $fulltext
 118          * @return string
 119          */
 120         function getIndexField( $fulltext ) {
 121                 return $fulltext ? 'si_text' : 'si_title';
 122         }
 123
 124         /**
 125          * Get the base part of the search query.
 126          * The actual match syntax will depend on the server
 127          * version; MySQL 3 and MySQL 4 have different capabilities
 128          * in their fulltext search indexes.
 129          *
 130          * @param string $filteredTerm
 131          * @param bool $fulltext
 132          * @return string
 133          * @private
 134          */
 135         function queryMain( $filteredTerm, $fulltext ) {
 136                 $match = $this->parseQuery( $filteredTerm, $fulltext );
 137                 $page        = $this->db->tableName( 'page' );
 138                 $searchindex = $this->db->tableName( 'searchindex' );
 139                 return 'SELECT page_id, page_namespace, page_title ' .
 140                         "FROM $page,$searchindex " .
 141                         'WHERE page_id=si_page AND ' . $match;
 142         }
 143
 144         /**
 145          * Create or update the search index record for the given page.
 146          * Title and text should be pre-processed.
 147          *
 148          * @param int $id
 149          * @param string $title
 150          * @param string $text
 151          */
 152         function update( $id, $title, $text ) {
 153                 $dbw=& wfGetDB( DB_MASTER );
 154                 $dbw->replace( 'searchindex',
 155                         array( 'si_page' ),
 156                         array(
 157                                 'si_page' => $id,
 158                                 'si_title' => $title,
 159                                 'si_text' => $text
 160                         ), 'SearchMySQL4::update' );
 161         }
 162
 163         /**
 164          * Update a search index record's title only.
 165          * Title should be pre-processed.
 166          *
 167          * @param int $id
 168          * @param string $title
 169          */
 170     function updateTitle( $id, $title ) {
 171                 $dbw =& wfGetDB( DB_MASTER );
 172
 173                 $dbw->update( 'searchindex',
 174                         array( 'si_title' => $title ),
 175                         array( 'si_page'  => $id ),
 176                         'SearchMySQL4::updateTitle',
 177                         array( $dbw->lowPriorityOption() ) );
 178         }
 179 }
 180
 181 /** @package MediaWiki */
 182 class MySQLSearchResultSet extends SearchResultSet {
 183         function MySQLSearchResultSet( $resultSet, $terms ) {
 184                 $this->mResultSet = $resultSet;
 185                 $this->mTerms = $terms;
 186         }
 187
 188         function termMatches() {
 189                 return $this->mTerms;
 190         }
 191
 192         function numRows() {
 193                 return $this->mResultSet->numRows();
 194         }
 195
 196         function next() {
 197                 $row = $this->mResultSet->fetchObject();
 198                 if( $row === false ) {
 199                         return false;
 200                 } else {
 201                         return new SearchResult( $row );
 202                 }
 203         }
 204 }
 205
 206 ?>