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Delete object from collection versus delete from JPQL

#1
greymattergreymatter
Joined on 2014-03-23

I'm a newbie, so this is a pretty fundamental question.

I'm not sure if there is a bi-directional relationship between the objects in memory and ObjectDB.  I know I can modify the objects and use persist() to write them to the database.  But does running a JPQL update or delete alter the in-memory objects?

There are cases where the JPQL syntax is more expressive than operating on a collection, but I'm not sure if that will alter my program state.  Will it?

Thanks,
Lee 

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#2
supportsupport
Joined on 2010-05-03

UPDATE and DELETE queries bypass the EntityManager entity object management, and accordingly break the synchronization between memory and database objects.

See these manual pages for more details:

After using these queries you may use refresh, or discard cached objects in the EntityManager and in the L2 cache. 

ObjectDB Support
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