The previous persisted data always being overlapped after the new persisting

Question

Supposed that I have this data on a table 'X' :

ID    UpdatedDate    ParentID
001   2015-01-01     1
002                  1
003                  1

The code is (I simplified the code) :

... 

@Autowired
private XDao xDao;

private void createTransaction(ParentData parentData) {
    List<XData> xDataList = xDao.getDataByParentIdAndUpdatedDateIsNull(parentData.getId());
    XData xData = null;

    // Then we get only the first row of the list
    if(xDataList != null && xDataList.size() > 0) {
        xData = xDataList.get(0);
    } else {
        return;
    }

    // Another transaction
    ...

    // Then we update the UpdatedDate
    xData.setUpdatedDate(new Date());
    xDao.saveAndFlush(xData);

    // And we call the createTransaction again until there is no more xData with a null UpdatedDate on a Parent ID
    createTransaction(parentData);
} 

But what I get is a never ending process, while I check the db, it's always afflicted each other data on the same parent id. So the db is something like :

The first iteration :

ID    UpdatedDate    ParentID
001   2015-01-01     1
002   2015-02-02     1
003                  1

The 2nd:

ID    UpdatedDate    ParentID
001   2015-01-01     1
002                  1
003   2015-02-02     1

The 3rd:

ID    UpdatedDate    ParentID
001   2015-01-01     1
002   2015-02-02     1
003                  1

etc. What's wrong?

---

This is the getDataByParentIdAndUpdatedDateIsNull class (I simplified the code) :

...

public static final String GET_DATA_BY_PARENTIDANDUPDATEDDATEISNULL = 
    "SELECT o FROM XData o " +
    "WHERE o.parentData.parentId = ?1 " +
    "      AND o.updatedDate IS NULL";

@Query(GET_DATA_BY_PARENTIDANDUPDATEDDATEISNULL)
public List<XData> getDataByParentIdAndUpdatedDateIsNull(Long parentId);

Answer 1

Can you share,

1) definition of XDao

2) what is your underlying data store

3) Are you using any of the ORM framework

4) are you using explicit @Transactional on your Repository/Service or the tx:annotation-driven?

The behavior would be different based on the combination of the above, but my guess would be either with service transaction boundary confusing with that of store OR Since the @Transactional mechanism is based on proxies, only 'external' method calls coming in through the proxy will be intercepted and your recursive call will not be going through the same AOP you might have set up for your createTransaction method.

Having said that, is it not possible to do something like this, instead of recursion:

for (XData xData : xDataList) {
    xData.setUpdatedDate(new Date());
    xData.saveAndFlush(xData);
}