BBP_Converter_Base::clean_passwords( $start )

	public function clean_passwords( $start ) {

		$has_delete = false;

		/** Delete bbconverter passwords **************************************/

		$query       = 'SELECT user_id, meta_value FROM ' . $this->wpdb->usermeta . ' WHERE meta_key = "_bbp_password" LIMIT ' . $start . ', ' . $this->max_rows;
		update_option( '_bbp_converter_query', $query );

		$bbconverter = $this->wpdb->get_results( $query, ARRAY_A );

		if ( !empty( $bbconverter ) ) {

			foreach ( $bbconverter as $value ) {
				if ( is_serialized( $value['meta_value'] ) ) {
					$this->wpdb->query( 'UPDATE ' . $this->wpdb->users . ' ' . 'SET user_pass = "" ' . 'WHERE ID = "' . $value['user_id'] . '"' );
				} else {
					$this->wpdb->query( 'UPDATE ' . $this->wpdb->users . ' ' . 'SET user_pass = "' . $value['meta_value'] . '" ' . 'WHERE ID = "' . $value['user_id'] . '"' );
					$this->wpdb->query( 'DELETE FROM ' . $this->wpdb->usermeta . ' WHERE meta_key = "_bbp_password" AND user_id = "' . $value['user_id'] . '"' );
				}
			}
			$has_delete = true;
		}

		return ! $has_delete;
	}