}
	type User struct {
		ID  int
		Cat struct {
			Name string
			Toy  Toy   `gorm:"polymorphic:Owner;"`
			Toys []Toy `gorm:"polymorphic:Owner;"`
		} `gorm:"embedded;embeddedPrefix:cat_"`
		Dog struct {
			ID     int
			Name   string
			UserID int
			Toy    Toy   `gorm:"polymorphic:Owner;"`
			Toys   []Toy `gorm:"polymorphic:Owner;"`
		}
		Toys []Toy `gorm:"polymorphic:Owner;"`
	}

		{
			"name":    "cat",
			"user_id": gorm.Expr("(?)", DB.Table("(?) as tmp", subQuery).Select("@uid:=id")),
		},
		{
			"name":    "dog",
			"user_id": gorm.Expr("@uid"),
		},
	})