Set                    func(context.Context, reflect.Value, interface{}) error
	Serializer             SerializerInterface
	NewValuePool           FieldNewValuePool

	// In some db (e.g. MySQL), Unique and UniqueIndex are indistinguishable.
	// When a column has a (not Mul) UniqueIndex, Migrator always reports its gorm.ColumnType is Unique.
	// It causes field unnecessarily migration.