}

func TestSubQuery(t *testing.T) {
	users := []User{
		{Name: "subquery_1", Age: 10},
		{Name: "subquery_2", Age: 20},
		{Name: "subquery_3", Age: 30},
		{Name: "subquery_4", Age: 40},
	}

	DB.Create(&users)

	if err := DB.Select("*").Where("name IN (?)", DB.Select("name").Table("users").Where("name LIKE ?", "subquery_%")).Find(&users).Error; err != nil {
		t.Fatalf("got error: %v", err)
	}

type ViewOption struct {
	Replace     bool   // If true, exec `CREATE`. If false, exec `CREATE OR REPLACE`
	CheckOption string // optional. e.g. `WITH [ CASCADED | LOCAL ] CHECK OPTION`
	Query       *DB    // required subquery.
}

// ColumnType column type interface
type ColumnType interface {
	Name() string
	DatabaseTypeName() string                 // varchar
	ColumnType() (columnType string, ok bool) // varchar(64)

	user := User{Name: "jinzhu"}

	DB.Create(&user)

	subQuery := DB.Table("users").Where("name=?", user.Name).Select("id")

	result := DB.Session(&gorm.Session{DryRun: true}).Model(&Pet{}).Create([]map[string]interface{}{
		{
			"name":    "cat",
			"user_id": gorm.Expr("(?)", DB.Table("(?) as tmp", subQuery).Select("@uid:=id")),
		},
		{
			"name":    "dog",
			"user_id": gorm.Expr("@uid"),

//	q := DB.Model(&User{})
//	DB.Debug().Migrator().CreateView("user_view", gorm.ViewOption{Query: q, Replace: true, CheckOption: "WITH CHECK OPTION"})
//
// [subquery]: https://gorm.io/docs/advanced_query.html#SubQuery
func (m Migrator) CreateView(name string, option gorm.ViewOption) error {
	if option.Query == nil {
		return gorm.ErrSubQueryRequired
	}

	sql := new(strings.Builder)