Skip to main content

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [List Home]
Re: [eclipselink-users] how to update entities with persisted entities

I want the groups in my importData.getCharacterisicGroups() to be updated with the persisted id, or the newly assigned id.

What I am seeing now, that only for new persited groups, the id is automatically updated (viewing importData.getCharacterisicGroups() in debugger perspective). But for groups that are already in de db (and had a result for characteristicGroupDAO.findGroupByExample(importGroup) ), the id is not updated and it stays 0.
For this I do nothing extra.

How is this possible, that the id is only updated for newly persisted groups.

What I want is each group in importData.getCharacterisicGroups() to automatically be updated with the persisted group.


christopher delahunt wrote:
Hello Leon,

I'm not sure I understand correctly. I'm guessing that ImportGroup, if existing, is detached and contains changes that you want persisted. I assume that findGroupByExample(importGroup) is just a simple query or find method that returns the managed instance of importGroup. The problem then would be that you pass this managed copy into the makePersistent. Since the managed copy doesn't have the changes, they are lost. You need to merge the detached copy into the managed copy using the em.merge at some point.

If this isn't the problem, please give more detail as to what data isn't being persisted and how you are actually finding and persisting your entities.

Best Regards,

Leon Derks wrote:
I am seeing a behaviour which I can not explain.

I have a list of groups (imported from an xml file)
Then I loop through these groups and check if they already exist in de db.
I want them to be updated with the persisted group.

In my debugger perspective I see that ids of new groups are updated with the newly assigned id. But the groups that are already in the db are not updated with the persisted id.

The makePersistent method does a persist if id == 0 or else the entity is merged.

What I want is that all importGroups are updated with either the persisted id, or a newly assigned id.
At the moment only new groups are updated with an id.

How is this possible?

See below for code.

//Loop through the groups
List<CharacteristicGroup> importGroups = importData.getCharacterisicGroups();
for(CharacteristicGroup importGroup : importGroups) {
   importGroup = updateWithPersistedCharacteristicGroup(importGroup);

private CharacteristicGroup updateWithPersistedCharacteristicGroup(CharacteristicGroup importGroup) { CharacteristicGroup persistedGroup = characteristicGroupDAO.findGroupByExample(importGroup);
   if(persistedGroup != null) {
        importGroup = persistedGroup;
   return importGroup;
eclipselink-users mailing list
eclipselink-users mailing list

__________ NOD32 3599 (20081110) Informatie __________

Dit bericht is gecontroleerd door het NOD32 Antivirus Systeem.

Back to the top