wikimedia / mediawiki

maintenance/renameDbPrefix.php

<?php

For compatibility and reusability of your code, PSR1 recommends that a file should introduce either new symbols (like classes, functions, etc.) or have side-effects (like outputting something, or including other files), but not both at the same time. The first symbol is defined on line 33 and the first side effect is on line 26.

/**
 * Change the prefix of database tables.
 * Run this script to after changing $wgDBprefix on a wiki.
 * The wiki will have to get downtime to do this correctly.
 *
 * 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 Maintenance
 */

require_once __DIR__ . '/Maintenance.php';

/**
 * Maintenance script that changes the prefix of database tables.
 *
 * @ingroup Maintenance
 */
class RenameDbPrefix extends Maintenance {
	public function __construct() {
		parent::__construct();
		$this->addOption( "old", "Old db prefix [0 for none]", true, true );
		$this->addOption( "new", "New db prefix [0 for none]", true, true );
	}

	public function getDbType() {
		return Maintenance::DB_ADMIN;
	}

	public function execute() {
		global $wgDBname;

		// Allow for no old prefix
		if ( $this->getOption( 'old', 0 ) === '0' ) {
			$old = '';
		} else {
			// Use nice safe, sane, prefixes
			preg_match( '/^[a-zA-Z]+_$/', $this->getOption( 'old' ), $m );
			$old = isset( $m[0] ) ? $m[0] : false;
		}
		// Allow for no new prefix
		if ( $this->getOption( 'new', 0 ) === '0' ) {
			$new = '';
		} else {
			// Use nice safe, sane, prefixes
			preg_match( '/^[a-zA-Z]+_$/', $this->getOption( 'new' ), $m );
			$new = isset( $m[0] ) ? $m[0] : false;
		}

		if ( $old === false || $new === false ) {
			$this->error( "Invalid prefix!", true );
		}
		if ( $old === $new ) {
			$this->output( "Same prefix. Nothing to rename!\n", true );
		}

		$this->output( "Renaming DB prefix for tables of $wgDBname from '$old' to '$new'\n" );
		$count = 0;

		$dbw = $this->getDB( DB_MASTER );
		$res = $dbw->query( "SHOW TABLES " . $dbw->buildLike( $old, $dbw->anyString() ) );
		foreach ( $res as $row ) {
			// XXX: odd syntax. MySQL outputs an oddly cased "Tables of X"
			// sort of message. Best not to try $row->x stuff...
			$fields = get_object_vars( $row );
			// Silly for loop over one field...
			foreach ( $fields as $table ) {
				// $old should be regexp safe ([a-zA-Z_])
				$newTable = preg_replace( '/^' . $old . '/', $new, $table );
				$this->output( "Renaming table $table to $newTable\n" );
				$dbw->query( "RENAME TABLE $table TO $newTable" );
			}
			$count++;
		}
		$this->output( "Done! [$count tables]\n" );
	}
}

$maintClass = "RenameDbPrefix";
require_once RUN_MAINTENANCE_IF_MAIN;