Nullable() (nullable bool, ok bool)
	Unique() (unique bool, ok bool)
	ScanType() reflect.Type
	Comment() (value string, ok bool)
	DefaultValue() (value string, ok bool)
}

type Index interface {
	Table() string
	Name() string
	Columns() []string
	PrimaryKey() (isPrimaryKey bool, ok bool)
	Unique() (unique bool, ok bool)
	Option() string
}

// TableType table type interface

	unique, ok := columnType.Unique()
	if !ok || field.PrimaryKey {
		return nil // skip primary key
	}
	// By default, ColumnType's Unique is not affected by UniqueIndex, so we don't care about UniqueIndex.
	return m.RunWithValue(value, func(stmt *gorm.Statement) error {
		// We're currently only receiving boolean values on `Unique` tag,
		// so the UniqueConstraint name is fixed