think\model\Relation::save PHP Метод

    public function save($data, array $pivot = [])
    {
        // 判断关联类型
        switch ($this->type) {
            case self::HAS_ONE:
            case self::BELONGS_TO:
            case self::HAS_MANY:
                if ($data instanceof Model) {
                    $data = $data->getData();
                }
                // 保存关联表数据
                $data[$this->foreignKey] = $this->parent->{$this->localKey};
                $model = new $this->model();
                return $model->save($data);
            case self::BELONGS_TO_MANY:
                // 保存关联表/中间表数据
                return $this->attach($data, $pivot);
        }
    }