protected function prepare_query() {

		global $wpdb;

		$from  = "FROM {$wpdb->prefix}lifterlms_quiz_attempts qa";
		$joins = $this->sql_joins();
		$where = $this->sql_where();

		if ( $this->get( 'count_only' ) ) {
			return "SELECT COUNT(*) AS total {$from} {$joins} {$where};";
		}

		if ( ! $this->get( 'no_found_rows' ) ) {
			$this->count_query = "SELECT COUNT(*) {$from} {$joins} {$where}";
		}

		return "SELECT qa.id {$from} {$joins} {$where} {$this->sql_orderby()} {$this->sql_limit()};";
	}