// arbitrary number of commands in fc within a transaction. On success the changes are committed; if an error occurs
// they are rolled back.
func (db *DB) Transaction(fc func(tx *DB) error, opts ...*sql.TxOptions) (err error) {
	panicked := true

	if committer, ok := db.Statement.ConnPool.(TxCommitter); ok && committer != nil {
		// nested transaction

	}
	for _, cbName := range callbackTypes {
		if methodValue := callBackToMethodValue(modelValue, cbName); methodValue.IsValid() {
			switch methodValue.Type().String() {
			case "func(*gorm.DB) error": // TODO hack
				reflect.Indirect(reflect.ValueOf(schema)).FieldByName(string(cbName)).SetBool(true)
			default:

}

func (association *Association) saveAssociation(clear bool, values ...interface{}) {
	var (
		reflectValue = association.DB.Statement.ReflectValue
		assignBacks  []assignBack // assign association values back to arguments after save
	)

	appendToRelations := func(source, rv reflect.Value, clear bool) {
		switch association.Relationship.Type {
		case schema.HasOne, schema.BelongsTo:
			switch rv.Kind() {