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Diffstat (limited to 'includes/search/SearchIBM_DB2.php')
| -rw-r--r-- | includes/search/SearchIBM_DB2.php | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/includes/search/SearchIBM_DB2.php b/includes/search/SearchIBM_DB2.php new file mode 100644 index 00000000..d7587186 --- /dev/null +++ b/includes/search/SearchIBM_DB2.php @@ -0,0 +1,224 @@ +<?php +# Copyright (C) 2004 Brion Vibber <brion@pobox.com> +# http://www.mediawiki.org/ +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License along +# with this program; if not, write to the Free Software Foundation, Inc., +# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. +# http://www.gnu.org/copyleft/gpl.html + +/** + * @file + * @ingroup Search + */ + +/** + * Search engine hook base class for IBM DB2 + * @ingroup Search + */ +class SearchIBM_DB2 extends SearchEngine { + function __construct($db) { + $this->db = $db; + } + + /** + * Perform a full text search query and return a result set. + * + * @param $term String: raw search term + * @return SqlSearchResultSet + */ + function searchText( $term ) { + $resultSet = $this->db->resultObject($this->db->query($this->getQuery($this->filter($term), true))); + return new SqlSearchResultSet($resultSet, $this->searchTerms); + } + + /** + * Perform a title-only search query and return a result set. + * + * @param $term String: taw search term + * @return SqlSearchResultSet + */ + function searchTitle($term) { + $resultSet = $this->db->resultObject($this->db->query($this->getQuery($this->filter($term), false))); + return new SqlSearchResultSet($resultSet, $this->searchTerms); + } + + + /** + * Return a partial WHERE clause to exclude redirects, if so set + * @return String + */ + function queryRedirect() { + if ($this->showRedirects) { + return ''; + } else { + return 'AND page_is_redirect=0'; + } + } + + /** + * Return a partial WHERE clause to limit the search to the given namespaces + * @return String + */ + function queryNamespaces() { + if( is_null($this->namespaces) ) + return ''; + $namespaces = implode(',', $this->namespaces); + if ($namespaces == '') { + $namespaces = '0'; + } + return 'AND page_namespace IN (' . $namespaces . ')'; + } + + /** + * Return a LIMIT clause to limit results on the query. + * @return String + */ + function queryLimit($sql) { + return $this->db->limitResult($sql, $this->limit, $this->offset); + } + + /** + * Does not do anything for generic search engine + * subclasses may define this though + * @return String + */ + function queryRanking($filteredTerm, $fulltext) { + // requires Net Search Extender or equivalent + // return ' ORDER BY score(1)'; + return ''; + } + + /** + * Construct the full SQL query to do the search. + * The guts shoulds be constructed in queryMain() + * @param string $filteredTerm String + * @param bool $fulltext Boolean + */ + function getQuery( $filteredTerm, $fulltext ) { + return $this->queryLimit($this->queryMain($filteredTerm, $fulltext) . ' ' . + $this->queryRedirect() . ' ' . + $this->queryNamespaces() . ' ' . + $this->queryRanking( $filteredTerm, $fulltext ) . ' '); + } + + + /** + * Picks which field to index on, depending on what type of query. + * @param $fulltext Boolean + * @return String + */ + function getIndexField($fulltext) { + return $fulltext ? 'si_text' : 'si_title'; + } + + /** + * Get the base part of the search query. + * + * @param string $filteredTerm String + * @param bool $fulltext Boolean + * @return String + */ + function queryMain( $filteredTerm, $fulltext ) { + $match = $this->parseQuery($filteredTerm, $fulltext); + $page = $this->db->tableName('page'); + $searchindex = $this->db->tableName('searchindex'); + return 'SELECT page_id, page_namespace, page_title ' . + "FROM $page,$searchindex " . + 'WHERE page_id=si_page AND ' . $match; + } + + /** @todo document */ + function parseQuery($filteredText, $fulltext) { + global $wgContLang; + $lc = SearchEngine::legalSearchChars(); + $this->searchTerms = array(); + + # FIXME: This doesn't handle parenthetical expressions. + $m = array(); + $q = array(); + + if (preg_match_all('/([-+<>~]?)(([' . $lc . ']+)(\*?)|"[^"]*")/', + $filteredText, $m, PREG_SET_ORDER)) { + foreach($m as $terms) { + + // Search terms in all variant forms, only + // apply on wiki with LanguageConverter + $temp_terms = $wgContLang->autoConvertToAllVariants( $terms[2] ); + if( is_array( $temp_terms )) { + $temp_terms = array_unique( array_values( $temp_terms )); + foreach( $temp_terms as $t ) + $q[] = $terms[1] . $wgContLang->normalizeForSearch( $t ); + } + else + $q[] = $terms[1] . $wgContLang->normalizeForSearch( $terms[2] ); + + if (!empty($terms[3])) { + $regexp = preg_quote( $terms[3], '/' ); + if ($terms[4]) + $regexp .= "[0-9A-Za-z_]+"; + } else { + $regexp = preg_quote(str_replace('"', '', $terms[2]), '/'); + } + $this->searchTerms[] = $regexp; + } + } + + $searchon = $this->db->strencode(join(',', $q)); + $field = $this->getIndexField($fulltext); + + // requires Net Search Extender or equivalent + //return " CONTAINS($field, '$searchon') > 0 "; + + return " lcase($field) LIKE lcase('%$searchon%')"; + } + + /** + * Create or update the search index record for the given page. + * Title and text should be pre-processed. + * + * @param $id Integer + * @param $title String + * @param $text String + */ + function update($id, $title, $text) { + $dbw = wfGetDB(DB_MASTER); + $dbw->replace('searchindex', + array('si_page'), + array( + 'si_page' => $id, + 'si_title' => $title, + 'si_text' => $text + ), 'SearchIBM_DB2::update' ); + // ? + //$dbw->query("CALL ctx_ddl.sync_index('si_text_idx')"); + //$dbw->query("CALL ctx_ddl.sync_index('si_title_idx')"); + } + + /** + * Update a search index record's title only. + * Title should be pre-processed. + * + * @param $id Integer + * @param $title String + */ + function updateTitle($id, $title) { + $dbw = wfGetDB(DB_MASTER); + + $dbw->update('searchindex', + array('si_title' => $title), + array('si_page' => $id), + 'SearchIBM_DB2::updateTitle', + array()); + } +} |