includes/installer/MysqlUpdater.php

   1 <?php
   2 /**
   3  * MySQL-specific updater.
   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  * @file
  21  * @ingroup Deployment
  22  */
  23
  24 /**
  25  * Mysql update list and mysql-specific update functions.
  26  *
  27  * @ingroup Deployment
  28  * @since 1.17
  29  */
  30 class MysqlUpdater extends DatabaseUpdater {
  31
  32         protected function getCoreUpdateList() {
  33                 return array(
  34                         // 1.2
  35                         array( 'addField', 'ipblocks', 'ipb_id', 'patch-ipblocks.sql' ),
  36                         array( 'addField', 'ipblocks', 'ipb_expiry', 'patch-ipb_expiry.sql' ),
  37                         array( 'doInterwikiUpdate' ),
  38                         array( 'doIndexUpdate' ),
  39                         array( 'addTable', 'hitcounter', 'patch-hitcounter.sql' ),
  40                         array( 'addField', 'recentchanges', 'rc_type', 'patch-rc_type.sql' ),
  41
  42                         // 1.3
  43                         array( 'addField', 'user', 'user_real_name', 'patch-user-realname.sql' ),
  44                         array( 'addTable', 'querycache', 'patch-querycache.sql' ),
  45                         array( 'addTable', 'objectcache', 'patch-objectcache.sql' ),
  46                         array( 'addTable', 'categorylinks', 'patch-categorylinks.sql' ),
  47                         array( 'doOldLinksUpdate' ),
  48                         array( 'doFixAncientImagelinks' ),
  49                         array( 'addField', 'recentchanges', 'rc_ip', 'patch-rc_ip.sql' ),
  50
  51                         // 1.4
  52                         array( 'addIndex', 'image', 'PRIMARY', 'patch-image_name_primary.sql' ),
  53                         array( 'addField', 'recentchanges', 'rc_id', 'patch-rc_id.sql' ),
  54                         array( 'addField', 'recentchanges', 'rc_patrolled', 'patch-rc-patrol.sql' ),
  55                         array( 'addTable', 'logging', 'patch-logging.sql' ),
  56                         array( 'addField', 'user', 'user_token', 'patch-user_token.sql' ),
  57                         array( 'addField', 'watchlist', 'wl_notificationtimestamp', 'patch-email-notification.sql' ),
  58                         array( 'doWatchlistUpdate' ),
  59                         array( 'dropField', 'user', 'user_emailauthenticationtimestamp',
  60                                 'patch-email-authentication.sql' ),
  61
  62                         // 1.5
  63                         array( 'doSchemaRestructuring' ),
  64                         array( 'addField', 'logging', 'log_params', 'patch-log_params.sql' ),
  65                         array( 'checkBin', 'logging', 'log_title', 'patch-logging-title.sql', ),
  66                         array( 'addField', 'archive', 'ar_rev_id', 'patch-archive-rev_id.sql' ),
  67                         array( 'addField', 'page', 'page_len', 'patch-page_len.sql' ),
  68                         array( 'dropField', 'revision', 'inverse_timestamp', 'patch-inverse_timestamp.sql' ),
  69                         array( 'addField', 'revision', 'rev_text_id', 'patch-rev_text_id.sql' ),
  70                         array( 'addField', 'revision', 'rev_deleted', 'patch-rev_deleted.sql' ),
  71                         array( 'addField', 'image', 'img_width', 'patch-img_width.sql' ),
  72                         array( 'addField', 'image', 'img_metadata', 'patch-img_metadata.sql' ),
  73                         array( 'addField', 'user', 'user_email_token', 'patch-user_email_token.sql' ),
  74                         array( 'addField', 'archive', 'ar_text_id', 'patch-archive-text_id.sql' ),
  75                         array( 'doNamespaceSize' ),
  76                         array( 'addField', 'image', 'img_media_type', 'patch-img_media_type.sql' ),
  77                         array( 'doPagelinksUpdate' ),
  78                         array( 'dropField', 'image', 'img_type', 'patch-drop_img_type.sql' ),
  79                         array( 'doUserUniqueUpdate' ),
  80                         array( 'doUserGroupsUpdate' ),
  81                         array( 'addField', 'site_stats', 'ss_total_pages', 'patch-ss_total_articles.sql' ),
  82                         array( 'addTable', 'user_newtalk', 'patch-usernewtalk2.sql' ),
  83                         array( 'addTable', 'transcache', 'patch-transcache.sql' ),
  84                         array( 'addField', 'interwiki', 'iw_trans', 'patch-interwiki-trans.sql' ),
  85
  86                         // 1.6
  87                         array( 'doWatchlistNull' ),
  88                         array( 'addIndex', 'logging', 'times', 'patch-logging-times-index.sql' ),
  89                         array( 'addField', 'ipblocks', 'ipb_range_start', 'patch-ipb_range_start.sql' ),
  90                         array( 'doPageRandomUpdate' ),
  91                         array( 'addField', 'user', 'user_registration', 'patch-user_registration.sql' ),
  92                         array( 'doTemplatelinksUpdate' ),
  93                         array( 'addTable', 'externallinks', 'patch-externallinks.sql' ),
  94                         array( 'addTable', 'job', 'patch-job.sql' ),
  95                         array( 'addField', 'site_stats', 'ss_images', 'patch-ss_images.sql' ),
  96                         array( 'addTable', 'langlinks', 'patch-langlinks.sql' ),
  97                         array( 'addTable', 'querycache_info', 'patch-querycacheinfo.sql' ),
  98                         array( 'addTable', 'filearchive', 'patch-filearchive.sql' ),
  99                         array( 'addField', 'ipblocks', 'ipb_anon_only', 'patch-ipb_anon_only.sql' ),
 100                         array( 'addIndex', 'recentchanges', 'rc_ns_usertext', 'patch-recentchanges-utindex.sql' ),
 101                         array( 'addIndex', 'recentchanges', 'rc_user_text', 'patch-rc_user_text-index.sql' ),
 102
 103                         // 1.9
 104                         array( 'addField', 'user', 'user_newpass_time', 'patch-user_newpass_time.sql' ),
 105                         array( 'addTable', 'redirect', 'patch-redirect.sql' ),
 106                         array( 'addTable', 'querycachetwo', 'patch-querycachetwo.sql' ),
 107                         array( 'addField', 'ipblocks', 'ipb_enable_autoblock', 'patch-ipb_optional_autoblock.sql' ),
 108                         array( 'doBacklinkingIndicesUpdate' ),
 109                         array( 'addField', 'recentchanges', 'rc_old_len', 'patch-rc_len.sql' ),
 110                         array( 'addField', 'user', 'user_editcount', 'patch-user_editcount.sql' ),
 111
 112                         // 1.10
 113                         array( 'doRestrictionsUpdate' ),
 114                         array( 'addField', 'logging', 'log_id', 'patch-log_id.sql' ),
 115                         array( 'addField', 'revision', 'rev_parent_id', 'patch-rev_parent_id.sql' ),
 116                         array( 'addField', 'page_restrictions', 'pr_id', 'patch-page_restrictions_sortkey.sql' ),
 117                         array( 'addField', 'revision', 'rev_len', 'patch-rev_len.sql' ),
 118                         array( 'addField', 'recentchanges', 'rc_deleted', 'patch-rc_deleted.sql' ),
 119                         array( 'addField', 'logging', 'log_deleted', 'patch-log_deleted.sql' ),
 120                         array( 'addField', 'archive', 'ar_deleted', 'patch-ar_deleted.sql' ),
 121                         array( 'addField', 'ipblocks', 'ipb_deleted', 'patch-ipb_deleted.sql' ),
 122                         array( 'addField', 'filearchive', 'fa_deleted', 'patch-fa_deleted.sql' ),
 123                         array( 'addField', 'archive', 'ar_len', 'patch-ar_len.sql' ),
 124
 125                         // 1.11
 126                         array( 'addField', 'ipblocks', 'ipb_block_email', 'patch-ipb_emailban.sql' ),
 127                         array( 'doCategorylinksIndicesUpdate' ),
 128                         array( 'addField', 'oldimage', 'oi_metadata', 'patch-oi_metadata.sql' ),
 129                         array( 'addIndex', 'archive', 'usertext_timestamp', 'patch-archive-user-index.sql' ),
 130                         array( 'addIndex', 'image', 'img_usertext_timestamp', 'patch-image-user-index.sql' ),
 131                         array( 'addIndex', 'oldimage', 'oi_usertext_timestamp', 'patch-oldimage-user-index.sql' ),
 132                         array( 'addField', 'archive', 'ar_page_id', 'patch-archive-page_id.sql' ),
 133                         array( 'addField', 'image', 'img_sha1', 'patch-img_sha1.sql' ),
 134
 135                         // 1.12
 136                         array( 'addTable', 'protected_titles', 'patch-protected_titles.sql' ),
 137
 138                         // 1.13
 139                         array( 'addField', 'ipblocks', 'ipb_by_text', 'patch-ipb_by_text.sql' ),
 140                         array( 'addTable', 'page_props', 'patch-page_props.sql' ),
 141                         array( 'addTable', 'updatelog', 'patch-updatelog.sql' ),
 142                         array( 'addTable', 'category', 'patch-category.sql' ),
 143                         array( 'doCategoryPopulation' ),
 144                         array( 'addField', 'archive', 'ar_parent_id', 'patch-ar_parent_id.sql' ),
 145                         array( 'addField', 'user_newtalk', 'user_last_timestamp', 'patch-user_last_timestamp.sql' ),
 146                         array( 'doPopulateParentId' ),
 147                         array( 'checkBin', 'protected_titles', 'pt_title', 'patch-pt_title-encoding.sql', ),
 148                         array( 'doMaybeProfilingMemoryUpdate' ),
 149                         array( 'doFilearchiveIndicesUpdate' ),
 150
 151                         // 1.14
 152                         array( 'addField', 'site_stats', 'ss_active_users', 'patch-ss_active_users.sql' ),
 153                         array( 'doActiveUsersInit' ),
 154                         array( 'addField', 'ipblocks', 'ipb_allow_usertalk', 'patch-ipb_allow_usertalk.sql' ),
 155
 156                         // 1.15
 157                         array( 'doUniquePlTlIl' ),
 158                         array( 'addTable', 'change_tag', 'patch-change_tag.sql' ),
 159                         array( 'addTable', 'tag_summary', 'patch-tag_summary.sql' ),
 160                         array( 'addTable', 'valid_tag', 'patch-valid_tag.sql' ),
 161
 162                         // 1.16
 163                         array( 'addTable', 'user_properties', 'patch-user_properties.sql' ),
 164                         array( 'addTable', 'log_search', 'patch-log_search.sql' ),
 165                         array( 'addField', 'logging', 'log_user_text', 'patch-log_user_text.sql' ),
 166                         # listed separately from the previous update because 1.16 was released without this update
 167                         array( 'doLogUsertextPopulation' ),
 168                         array( 'doLogSearchPopulation' ),
 169                         array( 'addTable', 'l10n_cache', 'patch-l10n_cache.sql' ),
 170                         array( 'addIndex', 'log_search', 'ls_field_val', 'patch-log_search-rename-index.sql' ),
 171                         array( 'addIndex', 'change_tag', 'change_tag_rc_tag', 'patch-change_tag-indexes.sql' ),
 172                         array( 'addField', 'redirect', 'rd_interwiki', 'patch-rd_interwiki.sql' ),
 173                         array( 'doUpdateTranscacheField' ),
 174                         array( 'doUpdateMimeMinorField' ),
 175
 176                         // 1.17
 177                         array( 'addTable', 'iwlinks', 'patch-iwlinks.sql' ),
 178                         array( 'addIndex', 'iwlinks', 'iwl_prefix_title_from', 'patch-rename-iwl_prefix.sql' ),
 179                         array( 'addField', 'updatelog', 'ul_value', 'patch-ul_value.sql' ),
 180                         array( 'addField', 'interwiki', 'iw_api', 'patch-iw_api_and_wikiid.sql' ),
 181                         array( 'dropIndex', 'iwlinks', 'iwl_prefix', 'patch-kill-iwl_prefix.sql' ),
 182                         array( 'addField', 'categorylinks', 'cl_collation', 'patch-categorylinks-better-collation.sql' ),
 183                         array( 'doClFieldsUpdate' ),
 184                         array( 'doCollationUpdate' ),
 185                         array( 'addTable', 'msg_resource', 'patch-msg_resource.sql' ),
 186                         array( 'addTable', 'module_deps', 'patch-module_deps.sql' ),
 187                         array( 'dropIndex', 'archive', 'ar_page_revid', 'patch-archive_kill_ar_page_revid.sql' ),
 188                         array( 'addIndex', 'archive', 'ar_revid', 'patch-archive_ar_revid.sql' ),
 189                         array( 'doLangLinksLengthUpdate' ),
 190
 191                         // 1.18
 192                         array( 'doUserNewTalkTimestampNotNull' ),
 193                         array( 'addIndex', 'user', 'user_email', 'patch-user_email_index.sql' ),
 194                         array( 'modifyField', 'user_properties', 'up_property', 'patch-up_property.sql' ),
 195                         array( 'addTable', 'uploadstash', 'patch-uploadstash.sql' ),
 196                         array( 'addTable', 'user_former_groups', 'patch-user_former_groups.sql' ),
 197
 198                         // 1.19
 199                         array( 'addIndex', 'logging', 'type_action', 'patch-logging-type-action-index.sql' ),
 200                         array( 'addField', 'revision', 'rev_sha1', 'patch-rev_sha1.sql' ),
 201                         array( 'doMigrateUserOptions' ),
 202                         array( 'dropField', 'user', 'user_options', 'patch-drop-user_options.sql' ),
 203                         array( 'addField', 'archive', 'ar_sha1', 'patch-ar_sha1.sql' ),
 204                         array( 'addIndex', 'page', 'page_redirect_namespace_len',
 205                                 'patch-page_redirect_namespace_len.sql' ),
 206                         array( 'addField', 'uploadstash', 'us_chunk_inx', 'patch-uploadstash_chunk.sql' ),
 207                         array( 'addfield', 'job', 'job_timestamp', 'patch-jobs-add-timestamp.sql' ),
 208
 209                         // 1.20
 210                         array( 'addIndex', 'revision', 'page_user_timestamp', 'patch-revision-user-page-index.sql' ),
 211                         array( 'addField', 'ipblocks', 'ipb_parent_block_id', 'patch-ipb-parent-block-id.sql' ),
 212                         array( 'addIndex', 'ipblocks', 'ipb_parent_block_id', 'patch-ipb-parent-block-id-index.sql' ),
 213                         array( 'dropField', 'category', 'cat_hidden', 'patch-cat_hidden.sql' ),
 214
 215                         // 1.21
 216                         array( 'addField', 'revision', 'rev_content_format', 'patch-revision-rev_content_format.sql' ),
 217                         array( 'addField', 'revision', 'rev_content_model', 'patch-revision-rev_content_model.sql' ),
 218                         array( 'addField', 'archive', 'ar_content_format', 'patch-archive-ar_content_format.sql' ),
 219                         array( 'addField', 'archive', 'ar_content_model', 'patch-archive-ar_content_model.sql' ),
 220                         array( 'addField', 'page', 'page_content_model', 'patch-page-page_content_model.sql' ),
 221                         array( 'dropField', 'site_stats', 'ss_admins', 'patch-drop-ss_admins.sql' ),
 222                         array( 'dropField', 'recentchanges', 'rc_moved_to_title', 'patch-rc_moved.sql' ),
 223                         array( 'addTable', 'sites', 'patch-sites.sql' ),
 224                         array( 'addField', 'filearchive', 'fa_sha1', 'patch-fa_sha1.sql' ),
 225                         array( 'addField', 'job', 'job_token', 'patch-job_token.sql' ),
 226                         array( 'addField', 'job', 'job_attempts', 'patch-job_attempts.sql' ),
 227                         array( 'doEnableProfiling' ),
 228                         array( 'addField', 'uploadstash', 'us_props', 'patch-uploadstash-us_props.sql' ),
 229                         array( 'modifyField', 'user_groups', 'ug_group', 'patch-ug_group-length-increase-255.sql' ),
 230                         array( 'modifyField', 'user_former_groups', 'ufg_group',
 231                                 'patch-ufg_group-length-increase-255.sql' ),
 232                         array( 'addIndex', 'page_props', 'pp_propname_page',
 233                                 'patch-page_props-propname-page-index.sql' ),
 234                         array( 'addIndex', 'image', 'img_media_mime', 'patch-img_media_mime-index.sql' ),
 235
 236                         // 1.22
 237                         array( 'doIwlinksIndexNonUnique' ),
 238                         array( 'addIndex', 'iwlinks', 'iwl_prefix_from_title',
 239                                 'patch-iwlinks-from-title-index.sql' ),
 240                         array( 'addField', 'archive', 'ar_id', 'patch-archive-ar_id.sql' ),
 241                         array( 'addField', 'externallinks', 'el_id', 'patch-externallinks-el_id.sql' ),
 242                         array( 'addField', 'recentchanges', 'rc_source', 'patch-rc_source.sql' ),
 243                 );
 244         }
 245
 246         /**
 247          * 1.4 betas were missing the 'binary' marker from logging.log_title,
 248          * which causes a collation mismatch error on joins in MySQL 4.1.
 249          *
 250          * @param string $table table name
 251          * @param string $field field name to check
 252          * @param string $patchFile path to the patch to correct the field
 253          */
 254         protected function checkBin( $table, $field, $patchFile ) {
 255                 if ( !$this->doTable( $table ) ) {
 256                         return true;
 257                 }
 258
 259                 $fieldInfo = $this->db->fieldInfo( $table, $field );
 260                 if ( $fieldInfo->isBinary() ) {
 261                         $this->output( "...$table table has correct $field encoding.\n" );
 262                 } else {
 263                         $this->applyPatch( $patchFile, false, "Fixing $field encoding on $table table" );
 264                 }
 265         }
 266
 267         /**
 268          * Check whether an index contain a field
 269          *
 270          * @param string $table table name
 271          * @param string $index index name to check
 272          * @param string $field field that should be in the index
 273          * @return Boolean
 274          */
 275         protected function indexHasField( $table, $index, $field ) {
 276                 if ( !$this->doTable( $table ) ) {
 277                         return true;
 278                 }
 279
 280                 $info = $this->db->indexInfo( $table, $index, __METHOD__ );
 281                 if ( $info ) {
 282                         foreach ( $info as $row ) {
 283                                 if ( $row->Column_name == $field ) {
 284                                         $this->output( "...index $index on table $table includes field $field.\n" );
 285
 286                                         return true;
 287                                 }
 288                         }
 289                 }
 290                 $this->output( "...index $index on table $table has no field $field; added.\n" );
 291
 292                 return false;
 293         }
 294
 295         /**
 296          * Check that interwiki table exists; if it doesn't source it
 297          */
 298         protected function doInterwikiUpdate() {
 299                 global $IP;
 300
 301                 if ( !$this->doTable( 'interwiki' ) ) {
 302                         return true;
 303                 }
 304
 305                 if ( $this->db->tableExists( "interwiki", __METHOD__ ) ) {
 306                         $this->output( "...already have interwiki table\n" );
 307
 308                         return;
 309                 }
 310
 311                 $this->applyPatch( 'patch-interwiki.sql', false, 'Creating interwiki table' );
 312                 $this->applyPatch(
 313                         "$IP/maintenance/interwiki.sql",
 314                         true,
 315                         'Adding default interwiki definitions'
 316                 );
 317         }
 318
 319         /**
 320          * Check that proper indexes are in place
 321          */
 322         protected function doIndexUpdate() {
 323                 $meta = $this->db->fieldInfo( 'recentchanges', 'rc_timestamp' );
 324                 if ( $meta === false ) {
 325                         throw new MWException( 'Missing rc_timestamp field of recentchanges table. Should not happen.' );
 326                 }
 327                 if ( $meta->isMultipleKey() ) {
 328                         $this->output( "...indexes seem up to 20031107 standards.\n" );
 329
 330                         return;
 331                 }
 332
 333                 $this->applyPatch( 'patch-indexes.sql', true, "Updating indexes to 20031107" );
 334         }
 335
 336         protected function doOldLinksUpdate() {
 337                 $cl = $this->maintenance->runChild( 'ConvertLinks' );
 338                 $cl->execute();
 339         }
 340
 341         protected function doFixAncientImagelinks() {
 342                 $info = $this->db->fieldInfo( 'imagelinks', 'il_from' );
 343                 if ( !$info || $info->type() !== 'string' ) {
 344                         $this->output( "...il_from OK\n" );
 345
 346                         return;
 347                 }
 348
 349                 $applied = $this->applyPatch(
 350                         'patch-fix-il_from.sql',
 351                         false,
 352                         'Fixing ancient broken imagelinks table.'
 353                 );
 354
 355                 if ( $applied ) {
 356                         $this->output( "NOTE: you will have to run maintenance/refreshLinks.php after this." );
 357                 }
 358         }
 359
 360         /**
 361          * Check if we need to add talk page rows to the watchlist
 362          */
 363         function doWatchlistUpdate() {
 364                 $talk = $this->db->selectField( 'watchlist', 'count(*)', 'wl_namespace & 1', __METHOD__ );
 365                 $nontalk = $this->db->selectField(
 366                         'watchlist',
 367                         'count(*)',
 368                         'NOT (wl_namespace & 1)',
 369                         __METHOD__
 370                 );
 371                 if ( $talk == $nontalk ) {
 372                         $this->output( "...watchlist talk page rows already present.\n" );
 373
 374                         return;
 375                 }
 376
 377                 $this->output( "Adding missing watchlist talk page rows... " );
 378                 $this->db->insertSelect( 'watchlist', 'watchlist',
 379                         array(
 380                                 'wl_user' => 'wl_user',
 381                                 'wl_namespace' => 'wl_namespace | 1',
 382                                 'wl_title' => 'wl_title',
 383                                 'wl_notificationtimestamp' => 'wl_notificationtimestamp'
 384                         ), array( 'NOT (wl_namespace & 1)' ), __METHOD__, 'IGNORE' );
 385                 $this->output( "done.\n" );
 386         }
 387
 388         function doSchemaRestructuring() {
 389                 if ( $this->db->tableExists( 'page', __METHOD__ ) ) {
 390                         $this->output( "...page table already exists.\n" );
 391
 392                         return;
 393                 }
 394
 395                 $this->output( "...converting from cur/old to page/revision/text DB structure.\n" );
 396                 $this->output( wfTimestamp( TS_DB ) );
 397                 $this->output( "......checking for duplicate entries.\n" );
 398
 399                 list( $cur, $old, $page, $revision, $text ) = $this->db->tableNamesN(
 400                         'cur',
 401                         'old',
 402                         'page',
 403                         'revision',
 404                         'text'
 405                 );
 406
 407                 $rows = $this->db->query( "
 408                         SELECT cur_title, cur_namespace, COUNT(cur_namespace) AS c
 409                         FROM $cur
 410                         GROUP BY cur_title, cur_namespace
 411                         HAVING c>1",
 412                         __METHOD__
 413                 );
 414
 415                 if ( $rows->numRows() > 0 ) {
 416                         $this->output( wfTimestamp( TS_DB ) );
 417                         $this->output( "......<b>Found duplicate entries</b>\n" );
 418                         $this->output( sprintf( "<b>      %-60s %3s %5s</b>\n", 'Title', 'NS', 'Count' ) );
 419                         $duplicate = array();
 420                         foreach ( $rows as $row ) {
 421                                 if ( !isset( $duplicate[$row->cur_namespace] ) ) {
 422                                         $duplicate[$row->cur_namespace] = array();
 423                                 }
 424
 425                                 $duplicate[$row->cur_namespace][] = $row->cur_title;
 426                                 $this->output( sprintf(
 427                                         "      %-60s %3s %5s\n",
 428                                         $row->cur_title, $row->cur_namespace,
 429                                         $row->c
 430                                 ) );
 431                         }
 432                         $sql = "SELECT cur_title, cur_namespace, cur_id, cur_timestamp FROM $cur WHERE ";
 433                         $firstCond = true;
 434                         foreach ( $duplicate as $ns => $titles ) {
 435                                 if ( $firstCond ) {
 436                                         $firstCond = false;
 437                                 } else {
 438                                         $sql .= ' OR ';
 439                                 }
 440                                 $sql .= "( cur_namespace = {$ns} AND cur_title in (";
 441                                 $first = true;
 442                                 foreach ( $titles as $t ) {
 443                                         if ( $first ) {
 444                                                 $sql .= $this->db->addQuotes( $t );
 445                                                 $first = false;
 446                                         } else {
 447                                                 $sql .= ', ' . $this->db->addQuotes( $t );
 448                                         }
 449                                 }
 450                                 $sql .= ") ) \n";
 451                         }
 452                         # By sorting descending, the most recent entry will be the first in the list.
 453                         # All following entries will be deleted by the next while-loop.
 454                         $sql .= 'ORDER BY cur_namespace, cur_title, cur_timestamp DESC';
 455
 456                         $rows = $this->db->query( $sql, __METHOD__ );
 457
 458                         $prev_title = $prev_namespace = false;
 459                         $deleteId = array();
 460
 461                         foreach ( $rows as $row ) {
 462                                 if ( $prev_title == $row->cur_title && $prev_namespace == $row->cur_namespace ) {
 463                                         $deleteId[] = $row->cur_id;
 464                                 }
 465                                 $prev_title = $row->cur_title;
 466                                 $prev_namespace = $row->cur_namespace;
 467                         }
 468                         $sql = "DELETE FROM $cur WHERE cur_id IN ( " . join( ',', $deleteId ) . ')';
 469                         $this->db->query( $sql, __METHOD__ );
 470                         $this->output( wfTimestamp( TS_DB ) );
 471                         $this->output( "......<b>Deleted</b> " . $this->db->affectedRows() . " records.\n" );
 472                 }
 473
 474                 $this->output( wfTimestamp( TS_DB ) );
 475                 $this->output( "......Creating tables.\n" );
 476                 $this->db->query( "CREATE TABLE $page (
 477                         page_id int(8) unsigned NOT NULL auto_increment,
 478                         page_namespace int NOT NULL,
 479                         page_title varchar(255) binary NOT NULL,
 480                         page_restrictions tinyblob NOT NULL,
 481                         page_counter bigint(20) unsigned NOT NULL default '0',
 482                         page_is_redirect tinyint(1) unsigned NOT NULL default '0',
 483                         page_is_new tinyint(1) unsigned NOT NULL default '0',
 484                         page_random real unsigned NOT NULL,
 485                         page_touched char(14) binary NOT NULL default '',
 486                         page_latest int(8) unsigned NOT NULL,
 487                         page_len int(8) unsigned NOT NULL,
 488
 489                         PRIMARY KEY page_id (page_id),
 490                         UNIQUE INDEX name_title (page_namespace,page_title),
 491                         INDEX (page_random),
 492                         INDEX (page_len)
 493                         ) ENGINE=InnoDB", __METHOD__ );
 494                 $this->db->query( "CREATE TABLE $revision (
 495                         rev_id int(8) unsigned NOT NULL auto_increment,
 496                         rev_page int(8) unsigned NOT NULL,
 497                         rev_comment tinyblob NOT NULL,
 498                         rev_user int(5) unsigned NOT NULL default '0',
 499                         rev_user_text varchar(255) binary NOT NULL default '',
 500                         rev_timestamp char(14) binary NOT NULL default '',
 501                         rev_minor_edit tinyint(1) unsigned NOT NULL default '0',
 502                         rev_deleted tinyint(1) unsigned NOT NULL default '0',
 503                         rev_len int(8) unsigned,
 504                         rev_parent_id int(8) unsigned default NULL,
 505                         PRIMARY KEY rev_page_id (rev_page, rev_id),
 506                         UNIQUE INDEX rev_id (rev_id),
 507                         INDEX rev_timestamp (rev_timestamp),
 508                         INDEX page_timestamp (rev_page,rev_timestamp),
 509                         INDEX user_timestamp (rev_user,rev_timestamp),
 510                         INDEX usertext_timestamp (rev_user_text,rev_timestamp)
 511                         ) ENGINE=InnoDB", __METHOD__ );
 512
 513                 $this->output( wfTimestamp( TS_DB ) );
 514                 $this->output( "......Locking tables.\n" );
 515                 $this->db->query(
 516                         "LOCK TABLES $page WRITE, $revision WRITE, $old WRITE, $cur WRITE",
 517                         __METHOD__
 518                 );
 519
 520                 $maxold = intval( $this->db->selectField( 'old', 'max(old_id)', '', __METHOD__ ) );
 521                 $this->output( wfTimestamp( TS_DB ) );
 522                 $this->output( "......maxold is {$maxold}\n" );
 523
 524                 $this->output( wfTimestamp( TS_DB ) );
 525                 global $wgLegacySchemaConversion;
 526                 if ( $wgLegacySchemaConversion ) {
 527                         // Create HistoryBlobCurStub entries.
 528                         // Text will be pulled from the leftover 'cur' table at runtime.
 529                         $this->output( "......Moving metadata from cur; using blob references to text in cur table.\n" );
 530                         $cur_text = "concat('O:18:\"historyblobcurstub\":1:{s:6:\"mCurId\";i:',cur_id,';}')";
 531                         $cur_flags = "'object'";
 532                 } else {
 533                         // Copy all cur text in immediately: this may take longer but avoids
 534                         // having to keep an extra table around.
 535                         $this->output( "......Moving text from cur.\n" );
 536                         $cur_text = 'cur_text';
 537                         $cur_flags = "''";
 538                 }
 539                 $this->db->query(
 540                         "INSERT INTO $old (old_namespace, old_title, old_text, old_comment, old_user,
 541                                 old_user_text, old_timestamp, old_minor_edit, old_flags)
 542                         SELECT cur_namespace, cur_title, $cur_text, cur_comment, cur_user, cur_user_text,
 543                                 cur_timestamp, cur_minor_edit, $cur_flags
 544                         FROM $cur",
 545                         __METHOD__
 546                 );
 547
 548                 $this->output( wfTimestamp( TS_DB ) );
 549                 $this->output( "......Setting up revision table.\n" );
 550                 $this->db->query(
 551                         "INSERT INTO $revision (rev_id, rev_page, rev_comment, rev_user,
 552                                 rev_user_text, rev_timestamp, rev_minor_edit)
 553                         SELECT old_id, cur_id, old_comment, old_user, old_user_text,
 554                                 old_timestamp, old_minor_edit
 555                         FROM $old,$cur WHERE old_namespace=cur_namespace AND old_title=cur_title",
 556                         __METHOD__
 557                 );
 558
 559                 $this->output( wfTimestamp( TS_DB ) );
 560                 $this->output( "......Setting up page table.\n" );
 561                 $this->db->query(
 562                         "INSERT INTO $page (page_id, page_namespace, page_title,
 563                                 page_restrictions, page_counter, page_is_redirect, page_is_new, page_random,
 564                                 page_touched, page_latest, page_len)
 565                         SELECT cur_id, cur_namespace, cur_title, cur_restrictions, cur_counter,
 566                                 cur_is_redirect, cur_is_new, cur_random, cur_touched, rev_id, LENGTH(cur_text)
 567                         FROM $cur,$revision
 568                         WHERE cur_id=rev_page AND rev_timestamp=cur_timestamp AND rev_id > {$maxold}",
 569                         __METHOD__
 570                 );
 571
 572                 $this->output( wfTimestamp( TS_DB ) );
 573                 $this->output( "......Unlocking tables.\n" );
 574                 $this->db->query( "UNLOCK TABLES", __METHOD__ );
 575
 576                 $this->output( wfTimestamp( TS_DB ) );
 577                 $this->output( "......Renaming old.\n" );
 578                 $this->db->query( "ALTER TABLE $old RENAME TO $text", __METHOD__ );
 579
 580                 $this->output( wfTimestamp( TS_DB ) );
 581                 $this->output( "...done.\n" );
 582         }
 583
 584         protected function doNamespaceSize() {
 585                 $tables = array(
 586                         'page' => 'page',
 587                         'archive' => 'ar',
 588                         'recentchanges' => 'rc',
 589                         'watchlist' => 'wl',
 590                         'querycache' => 'qc',
 591                         'logging' => 'log',
 592                 );
 593                 foreach ( $tables as $table => $prefix ) {
 594                         $field = $prefix . '_namespace';
 595
 596                         $tablename = $this->db->tableName( $table );
 597                         $result = $this->db->query( "SHOW COLUMNS FROM $tablename LIKE '$field'", __METHOD__ );
 598                         $info = $this->db->fetchObject( $result );
 599
 600                         if ( substr( $info->Type, 0, 3 ) == 'int' ) {
 601                                 $this->output( "...$field is already a full int ($info->Type).\n" );
 602                         } else {
 603                                 $this->output( "Promoting $field from $info->Type to int... " );
 604                                 $this->db->query( "ALTER TABLE $tablename MODIFY $field int NOT NULL", __METHOD__ );
 605                                 $this->output( "done.\n" );
 606                         }
 607                 }
 608         }
 609
 610         protected function doPagelinksUpdate() {
 611                 if ( $this->db->tableExists( 'pagelinks', __METHOD__ ) ) {
 612                         $this->output( "...already have pagelinks table.\n" );
 613
 614                         return;
 615                 }
 616
 617                 $this->applyPatch(
 618                         'patch-pagelinks.sql',
 619                         false,
 620                         'Converting links and brokenlinks tables to pagelinks'
 621                 );
 622
 623                 global $wgContLang;
 624                 foreach ( MWNamespace::getCanonicalNamespaces() as $ns => $name ) {
 625                         if ( $ns == 0 ) {
 626                                 continue;
 627                         }
 628
 629                         $this->output( "Cleaning up broken links for namespace $ns... " );
 630
 631                         $pagelinks = $this->db->tableName( 'pagelinks' );
 632                         $name = $wgContLang->getNsText( $ns );
 633                         $prefix = $this->db->strencode( $name );
 634                         $likeprefix = str_replace( '_', '\\_', $prefix );
 635
 636                         $sql = "UPDATE $pagelinks
 637                                            SET pl_namespace=$ns,
 638                                                    pl_title=TRIM(LEADING '$prefix:' FROM pl_title)
 639                                          WHERE pl_namespace=0
 640                                            AND pl_title LIKE '$likeprefix:%'";
 641
 642                         $this->db->query( $sql, __METHOD__ );
 643                         $this->output( "done.\n" );
 644                 }
 645         }
 646
 647         protected function doUserUniqueUpdate() {
 648                 if ( !$this->doTable( 'user' ) ) {
 649                         return true;
 650                 }
 651
 652                 $duper = new UserDupes( $this->db, array( $this, 'output' ) );
 653                 if ( $duper->hasUniqueIndex() ) {
 654                         $this->output( "...already have unique user_name index.\n" );
 655
 656                         return;
 657                 }
 658
 659                 if ( !$duper->clearDupes() ) {
 660                         $this->output( "WARNING: This next step will probably fail due to unfixed duplicates...\n" );
 661                 }
 662                 $this->applyPatch( 'patch-user_nameindex.sql', false, "Adding unique index on user_name" );
 663         }
 664
 665         protected function doUserGroupsUpdate() {
 666                 if ( !$this->doTable( 'user_groups' ) ) {
 667                         return true;
 668                 }
 669
 670                 if ( $this->db->tableExists( 'user_groups', __METHOD__ ) ) {
 671                         $info = $this->db->fieldInfo( 'user_groups', 'ug_group' );
 672                         if ( $info->type() == 'int' ) {
 673                                 $oldug = $this->db->tableName( 'user_groups' );
 674                                 $newug = $this->db->tableName( 'user_groups_bogus' );
 675                                 $this->output( "user_groups table exists but is in bogus intermediate " .
 676                                         "format. Renaming to $newug... " );
 677                                 $this->db->query( "ALTER TABLE $oldug RENAME TO $newug", __METHOD__ );
 678                                 $this->output( "done.\n" );
 679
 680                                 $this->applyPatch( 'patch-user_groups.sql', false, "Re-adding fresh user_groups table" );
 681
 682                                 $this->output( "***\n" );
 683                                 $this->output( "*** WARNING: You will need to manually fix up user " .
 684                                         "permissions in the user_groups\n" );
 685                                 $this->output( "*** table. Old 1.5 alpha versions did some pretty funky stuff...\n" );
 686                                 $this->output( "***\n" );
 687                         } else {
 688                                 $this->output( "...user_groups table exists and is in current format.\n" );
 689                         }
 690
 691                         return;
 692                 }
 693
 694                 $this->applyPatch( 'patch-user_groups.sql', false, "Adding user_groups table" );
 695
 696                 if ( !$this->db->tableExists( 'user_rights', __METHOD__ ) ) {
 697                         if ( $this->db->fieldExists( 'user', 'user_rights', __METHOD__ ) ) {
 698                                 $this->db->applyPatch(
 699                                         'patch-user_rights.sql',
 700                                         false,
 701                                         'Upgrading from a 1.3 or older database? Breaking out user_rights for conversion'
 702                                 );
 703                         } else {
 704                                 $this->output( "*** WARNING: couldn't locate user_rights table or field for upgrade.\n" );
 705                                 $this->output( "*** You may need to manually configure some sysops by manipulating\n" );
 706                                 $this->output( "*** the user_groups table.\n" );
 707
 708                                 return;
 709                         }
 710                 }
 711
 712                 $this->output( "Converting user_rights table to user_groups... " );
 713                 $result = $this->db->select( 'user_rights',
 714                         array( 'ur_user', 'ur_rights' ),
 715                         array( "ur_rights != ''" ),
 716                         __METHOD__ );
 717
 718                 foreach ( $result as $row ) {
 719                         $groups = array_unique(
 720                                 array_map( 'trim',
 721                                         explode( ',', $row->ur_rights ) ) );
 722
 723                         foreach ( $groups as $group ) {
 724                                 $this->db->insert( 'user_groups',
 725                                         array(
 726                                                 'ug_user' => $row->ur_user,
 727                                                 'ug_group' => $group ),
 728                                         __METHOD__ );
 729                         }
 730                 }
 731                 $this->output( "done.\n" );
 732         }
 733
 734         /**
 735          * Make sure wl_notificationtimestamp can be NULL,
 736          * and update old broken items.
 737          */
 738         protected function doWatchlistNull() {
 739                 $info = $this->db->fieldInfo( 'watchlist', 'wl_notificationtimestamp' );
 740                 if ( !$info ) {
 741                         return;
 742                 }
 743                 if ( $info->isNullable() ) {
 744                         $this->output( "...wl_notificationtimestamp is already nullable.\n" );
 745
 746                         return;
 747                 }
 748
 749                 $this->applyPatch(
 750                         'patch-watchlist-null.sql',
 751                         false,
 752                         'Making wl_notificationtimestamp nullable'
 753                 );
 754         }
 755
 756         /**
 757          * Set page_random field to a random value where it is equals to 0.
 758          *
 759          * @see bug 3946
 760          */
 761         protected function doPageRandomUpdate() {
 762                 $page = $this->db->tableName( 'page' );
 763                 $this->db->query( "UPDATE $page SET page_random = RAND() WHERE page_random = 0", __METHOD__ );
 764                 $rows = $this->db->affectedRows();
 765
 766                 if ( $rows ) {
 767                         $this->output( "Set page_random to a random value on $rows rows where it was set to 0\n" );
 768                 } else {
 769                         $this->output( "...no page_random rows needed to be set\n" );
 770                 }
 771         }
 772
 773         protected function doTemplatelinksUpdate() {
 774                 if ( $this->db->tableExists( 'templatelinks', __METHOD__ ) ) {
 775                         $this->output( "...templatelinks table already exists\n" );
 776
 777                         return;
 778                 }
 779
 780                 $this->applyPatch( 'patch-templatelinks.sql', false, "Creating templatelinks table" );
 781
 782                 $this->output( "Populating...\n" );
 783                 if ( wfGetLB()->getServerCount() > 1 ) {
 784                         // Slow, replication-friendly update
 785                         $res = $this->db->select( 'pagelinks', array( 'pl_from', 'pl_namespace', 'pl_title' ),
 786                                 array( 'pl_namespace' => NS_TEMPLATE ), __METHOD__ );
 787                         $count = 0;
 788                         foreach ( $res as $row ) {
 789                                 $count = ( $count + 1 ) % 100;
 790                                 if ( $count == 0 ) {
 791                                         wfWaitForSlaves();
 792                                 }
 793                                 $this->db->insert( 'templatelinks',
 794                                         array(
 795                                                 'tl_from' => $row->pl_from,
 796                                                 'tl_namespace' => $row->pl_namespace,
 797                                                 'tl_title' => $row->pl_title,
 798                                         ), __METHOD__
 799                                 );
 800                         }
 801                 } else {
 802                         // Fast update
 803                         $this->db->insertSelect( 'templatelinks', 'pagelinks',
 804                                 array(
 805                                         'tl_from' => 'pl_from',
 806                                         'tl_namespace' => 'pl_namespace',
 807                                         'tl_title' => 'pl_title'
 808                                 ), array(
 809                                         'pl_namespace' => 10
 810                                 ), __METHOD__
 811                         );
 812                 }
 813                 $this->output( "Done. Please run maintenance/refreshLinks.php for a more " .
 814                         "thorough templatelinks update.\n" );
 815         }
 816
 817         protected function doBacklinkingIndicesUpdate() {
 818                 if ( !$this->indexHasField( 'pagelinks', 'pl_namespace', 'pl_from' ) ||
 819                         !$this->indexHasField( 'templatelinks', 'tl_namespace', 'tl_from' ) ||
 820                         !$this->indexHasField( 'imagelinks', 'il_to', 'il_from' )
 821                 ) {
 822                         $this->applyPatch( 'patch-backlinkindexes.sql', false, "Updating backlinking indices" );
 823                 }
 824         }
 825
 826         /**
 827          * Adding page_restrictions table, obsoleting page.page_restrictions.
 828          * Migrating old restrictions to new table
 829          * -- Andrew Garrett, January 2007.
 830          */
 831         protected function doRestrictionsUpdate() {
 832                 if ( $this->db->tableExists( 'page_restrictions', __METHOD__ ) ) {
 833                         $this->output( "...page_restrictions table already exists.\n" );
 834
 835                         return;
 836                 }
 837
 838                 $this->applyPatch(
 839                         'patch-page_restrictions.sql',
 840                         false,
 841                         'Creating page_restrictions table (1/2)'
 842                 );
 843                 $this->applyPatch(
 844                         'patch-page_restrictions_sortkey.sql',
 845                         false,
 846                         'Creating page_restrictions table (2/2)'
 847                 );
 848                 $this->output( "done.\n" );
 849
 850                 $this->output( "Migrating old restrictions to new table...\n" );
 851                 $task = $this->maintenance->runChild( 'UpdateRestrictions' );
 852                 $task->execute();
 853         }
 854
 855         protected function doCategorylinksIndicesUpdate() {
 856                 if ( !$this->indexHasField( 'categorylinks', 'cl_sortkey', 'cl_from' ) ) {
 857                         $this->applyPatch( 'patch-categorylinksindex.sql', false, "Updating categorylinks Indices" );
 858                 }
 859         }
 860
 861         protected function doCategoryPopulation() {
 862                 if ( $this->updateRowExists( 'populate category' ) ) {
 863                         $this->output( "...category table already populated.\n" );
 864
 865                         return;
 866                 }
 867
 868                 $this->output(
 869                         "Populating category table, printing progress markers. " .
 870                         "For large databases, you\n" .
 871                         "may want to hit Ctrl-C and do this manually with maintenance/\n" .
 872                         "populateCategory.php.\n"
 873                 );
 874                 $task = $this->maintenance->runChild( 'PopulateCategory' );
 875                 $task->execute();
 876                 $this->output( "Done populating category table.\n" );
 877         }
 878
 879         protected function doPopulateParentId() {
 880                 if ( !$this->updateRowExists( 'populate rev_parent_id' ) ) {
 881                         $this->output(
 882                                 "Populating rev_parent_id fields, printing progress markers. For large\n" .
 883                                 "databases, you may want to hit Ctrl-C and do this manually with\n" .
 884                                 "maintenance/populateParentId.php.\n" );
 885
 886                         $task = $this->maintenance->runChild( 'PopulateParentId' );
 887                         $task->execute();
 888                 }
 889         }
 890
 891         protected function doEnableProfiling() {
 892                 global $wgProfileToDatabase;
 893
 894                 if ( !$this->doTable( 'profiling' ) ) {
 895                         return true;
 896                 }
 897
 898                 if ( $wgProfileToDatabase === true && !$this->db->tableExists( 'profiling', __METHOD__ ) ) {
 899                         $this->applyPatch( 'patch-profiling.sql', false, 'Add profiling table' );
 900                 }
 901         }
 902
 903         protected function doMaybeProfilingMemoryUpdate() {
 904                 if ( !$this->doTable( 'profiling' ) ) {
 905                         return true;
 906                 }
 907
 908                 if ( !$this->db->tableExists( 'profiling', __METHOD__ ) ) {
 909                         return true;
 910                 } elseif ( $this->db->fieldExists( 'profiling', 'pf_memory', __METHOD__ ) ) {
 911                         $this->output( "...profiling table has pf_memory field.\n" );
 912
 913                         return true;
 914                 }
 915
 916                 return $this->applyPatch(
 917                         'patch-profiling-memory.sql',
 918                         false,
 919                         'Adding pf_memory field to table profiling'
 920                 );
 921         }
 922
 923         protected function doFilearchiveIndicesUpdate() {
 924                 $info = $this->db->indexInfo( 'filearchive', 'fa_user_timestamp', __METHOD__ );
 925                 if ( !$info ) {
 926                         $this->applyPatch( 'patch-filearchive-user-index.sql', false, "Updating filearchive indices" );
 927                 }
 928
 929                 return true;
 930         }
 931
 932         protected function doUniquePlTlIl() {
 933                 $info = $this->db->indexInfo( 'pagelinks', 'pl_namespace' );
 934                 if ( is_array( $info ) && !$info[0]->Non_unique ) {
 935                         $this->output( "...pl_namespace, tl_namespace, il_to indices are already UNIQUE.\n" );
 936
 937                         return true;
 938                 }
 939                 if ( $this->skipSchema ) {
 940                         $this->output( "...skipping schema change (making pl_namespace, tl_namespace " .
 941                                 "and il_to indices UNIQUE).\n" );
 942
 943                         return false;
 944                 }
 945
 946                 return $this->applyPatch(
 947                         'patch-pl-tl-il-unique.sql',
 948                         false,
 949                         'Making pl_namespace, tl_namespace and il_to indices UNIQUE'
 950                 );
 951         }
 952
 953         protected function doUpdateMimeMinorField() {
 954                 if ( $this->updateRowExists( 'mime_minor_length' ) ) {
 955                         $this->output( "...*_mime_minor fields are already long enough.\n" );
 956
 957                         return;
 958                 }
 959
 960                 $this->applyPatch(
 961                         'patch-mime_minor_length.sql',
 962                         false,
 963                         'Altering all *_mime_minor fields to 100 bytes in size'
 964                 );
 965         }
 966
 967         protected function doClFieldsUpdate() {
 968                 if ( $this->updateRowExists( 'cl_fields_update' ) ) {
 969                         $this->output( "...categorylinks up-to-date.\n" );
 970
 971                         return;
 972                 }
 973
 974                 $this->applyPatch(
 975                         'patch-categorylinks-better-collation2.sql',
 976                         false,
 977                         'Updating categorylinks (again)'
 978                 );
 979         }
 980
 981         protected function doLangLinksLengthUpdate() {
 982                 $langlinks = $this->db->tableName( 'langlinks' );
 983                 $res = $this->db->query( "SHOW COLUMNS FROM $langlinks LIKE 'll_lang'" );
 984                 $row = $this->db->fetchObject( $res );
 985
 986                 if ( $row && $row->Type == "varbinary(10)" ) {
 987                         $this->applyPatch(
 988                                 'patch-langlinks-ll_lang-20.sql',
 989                                 false,
 990                                 'Updating length of ll_lang in langlinks'
 991                         );
 992                 } else {
 993                         $this->output( "...ll_lang is up-to-date.\n" );
 994                 }
 995         }
 996
 997         protected function doUserNewTalkTimestampNotNull() {
 998                 if ( !$this->doTable( 'user_newtalk' ) ) {
 999                         return true;
1000                 }
1001
1002                 $info = $this->db->fieldInfo( 'user_newtalk', 'user_last_timestamp' );
1003                 if ( $info === false ) {
1004                         return;
1005                 }
1006                 if ( $info->isNullable() ) {
1007                         $this->output( "...user_last_timestamp is already nullable.\n" );
1008
1009                         return;
1010                 }
1011
1012                 $this->applyPatch(
1013                         'patch-user-newtalk-timestamp-null.sql',
1014                         false,
1015                         'Making user_last_timestamp nullable'
1016                 );
1017         }
1018
1019         protected function doIwlinksIndexNonUnique() {
1020                 $info = $this->db->indexInfo( 'iwlinks', 'iwl_prefix_title_from' );
1021                 if ( is_array( $info ) && $info[0]->Non_unique ) {
1022                         $this->output( "...iwl_prefix_title_from index is already non-UNIQUE.\n" );
1023
1024                         return true;
1025                 }
1026                 if ( $this->skipSchema ) {
1027                         $this->output( "...skipping schema change (making iwl_prefix_title_from index non-UNIQUE).\n" );
1028
1029                         return false;
1030                 }
1031
1032                 return $this->applyPatch(
1033                         'patch-iwl_prefix_title_from-non-unique.sql',
1034                         false,
1035                         'Making iwl_prefix_title_from index non-UNIQUE'
1036                 );
1037         }
1038 }