[mybatis] plus nest exception

[Alice52]

1. saveBatch: mybatis-plus 为了可以保证事务所以添加了 @Transactional 注解
2. 如果外层使用 @Transactional + try..catch 就可能引起嵌套事务报错

   Transaction rolled back because it has been marked as rollback-only

3. sample code

    @Transactional(rollbackFor = Exception.class)
       public Boolean xxx(xxx dto) {
           list1 = .....;
           try {
               saveBatch(list1); // 报错会 marked as rollback-only
           } catch (Exception e) {
               if (e instanceof DuplicateKeyException) {
                     // 此时这个事务是不能提交的
                      The database saves the filtered list1 in batches;
               }
           }
   }

4. Workaround
   • saveBatch 上的 @Transactional 注解删
   • Set the '@Transactional' annotation for mybatis-plus to set the transaction propagation mechanism to: REQUIRES_NEW or NESTED
   • 自己写批量 xml SQL