maintenance/oracle/alterSharedConstraints.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  * @ingroup Maintenance
  20  */
  21
  22 use Wikimedia\Rdbms\DBQueryError;
  23
  24 /**
  25  * When using shared tables that are referenced by foreign keys on local
  26  * tables you have to change the constraints on local tables.
  27  *
  28  * The shared tables have to have GRANT REFERENCE on shared tables to local schema
  29  * i.e.: GRANT REFERENCES (user_id) ON mwuser TO hubclient;
  30  */
  31
  32 require_once __DIR__ . '/../Maintenance.php';
  33
  34 class AlterSharedConstraints extends Maintenance {
  35         public function __construct() {
  36                 parent::__construct();
  37                 $this->addDescription( 'Alter foreign key to reference master tables in shared database setup.' );
  38         }
  39
  40         public function getDbType() {
  41                 return Maintenance::DB_ADMIN;
  42         }
  43
  44         public function execute() {
  45                 global $wgSharedDB, $wgSharedTables, $wgSharedPrefix, $wgDBprefix;
  46
  47                 if ( $wgSharedDB == null ) {
  48                         $this->output( "Database sharing is not enabled\n" );
  49
  50                         return;
  51                 }
  52
  53                 $dbw = $this->getDB( DB_MASTER );
  54                 foreach ( $wgSharedTables as $table ) {
  55                         $stable = $dbw->tableNameInternal( $table );
  56                         if ( $wgSharedPrefix != null ) {
  57                                 $ltable = preg_replace( "/^$wgSharedPrefix(.*)/i", "$wgDBprefix\\1", $stable );
  58                         } else {
  59                                 $ltable = "{$wgDBprefix}{$stable}";
  60                         }
  61
  62                         $result = $dbw->query( "SELECT uc.constraint_name, uc.table_name, ucc.column_name,
  63                                                 uccpk.table_name pk_table_name, uccpk.column_name pk_column_name,
  64                                                 uc.delete_rule, uc.deferrable, uc.deferred
  65                                         FROM user_constraints uc, user_cons_columns ucc, user_cons_columns uccpk
  66                                         WHERE uc.constraint_type = 'R'
  67                                                 AND ucc.constraint_name = uc.constraint_name
  68                                                 AND uccpk.constraint_name = uc.r_constraint_name
  69                                                 AND uccpk.table_name = '$ltable'" );
  70
  71                         while ( ( $row = $result->fetchRow() ) !== false ) {
  72                                 $this->output( "Altering {$row['constraint_name']} ..." );
  73
  74                                 try {
  75                                         $dbw->query( "ALTER TABLE {$row['table_name']}
  76                                                         DROP CONSTRAINT {$wgDBprefix}{$row['constraint_name']}" );
  77                                 } catch ( DBQueryError $exdb ) {
  78                                         if ( $exdb->errno != 2443 ) {
  79                                                 throw $exdb;
  80                                         }
  81                                 }
  82
  83                                 $deleteRule = $row['delete_rule'] == 'NO ACTION' ? '' : "ON DELETE {$row['delete_rule']}";
  84                                 $dbw->query( "ALTER TABLE {$row['table_name']}
  85                                                 ADD CONSTRAINT {$wgDBprefix}{$row['constraint_name']}
  86                                                 FOREIGN KEY ({$row['column_name']})
  87                                                 REFERENCES {$wgSharedDB}.$stable({$row['pk_column_name']})
  88                                                 {$deleteRule} {$row['deferrable']} INITIALLY {$row['deferred']}" );
  89
  90                                 $this->output( "DONE\n" );
  91                         }
  92                 }
  93         }
  94 }
  95
  96 $maintClass = "AlterSharedConstraints";
  97 require_once RUN_MAINTENANCE_IF_MAIN;