public function execute( $par ) {
		global $wgOut, $wgUser;

		# only sysops and bureaucrats can update the DB
		if ( !$this->userCanExecute( $wgUser ) ) {
			$wgOut->addHTML( 'You have to be a member of the following group(s) to perform web install:' . implode( ', ', $this->allowed_groups ) );
			return;
		}
		# display update result
		$wgOut->addHTML( qp_SchemaUpdater::checkAndUpdate() );
	}