About detach

forum_thread

Import data from MySQL

Hi, I tried the objectdb in my research, find it very easy to handle without setting up xml files. However, I cannot find the import/export functions between other database, then how can I transfer mysql data into objectdb? When I use explorer.exe to browse the database in objectdb, eclipse tells me another app occupy it, then how can objectdb support multi-thread? ... retrieve old data from MySQL using JPA as entity objects, detach the retrieved entity objects and then persist them into ObjectDB. ...

 
page

What is new in ObjectDB 2.0?

... result sort. Improved query optimization engine. Detach / Attach. Support of persistent classes that are not enhanced. ...

 
forum_thread

Removing an entity throws exception

Hi all, I'm testing ObjectDB for my project, but I have troubles with it. At this time I'm not able to remove customer entity, when it's read by a query (it's attached), it throws this exception: Exception in thread "AWT-EventQueue-0" java.lang.RuntimeException: com.objectdb.o._RollbackException: Failed to commit transaction: 51 ... #1 2011-06-08 14:02 Hi all, I'm testing ObjectDB for my project, but I have troubles with it. At this time I'm not ab ...

 
forum_thread

@Entity saved in Tomcat session - problem

Hi, I have found a problem, when storing @Entity object in Tomcat session. When starting or stopping Tomcat, I get nasty exception - please check attached log. Strange thing is, that after this exception everything works perfectly fine. The problem appears after using Enhancer. The nasty solution is to create copy of @Entity class as normal POJO and use it to store in session. The problem is, that we need the same logic for temporary users (without storing in DB) and permanent users (stored in database). A separate POJO makes the whole logic quite complicated. #1 2010-12-13 14:42 Hi, I have found a problem, when storing @Entity object in Tomcat session. When starting or stopping ...

 
forum_thread

Can't get arraylist/vector type attributes

I have a class that contains some attributes of type Vector (also tried with ArrayList and same happens). When I try to get an object from that class doing using the find method it works fine, I get the object. But when I call the close method to close the EntityManager the information from the Vector dissapears and I get an empty vector. ... FetchType.EAGER ). See also "objectdb.temp.no-detach" as a possible quick workaround. ObjectDB ...

 
api-jdo

getDetachmentRoots()

Get the roots for DetachAllOnCommit.(Method of javax.jdo.FetchPlan)

 
api-jdo

FetchPlan.DETACH_UNLOAD_FIELDS

For use with PersistenceManager.detachCopy and setDetachmentOptions.(Static Field of javax.jdo.FetchPlan)

 
issue

Use temporary files to enable very large transactions

We have transactions in which many objects are created. These objects are no longer needed in the current transaction after creation. Unfortunately, we will receive an OutOfMemory exception because the objects are kept in the first level cache of ObjectDB. In the forum thread http://www.objectdb.com/database/forum/921 on post #4 you wrote, that ObjectDB should support very large transactions in further version. Can you implement it that ObjectDB used temporary files? ... objects from the first level cache (by flush() and detach()). But an array of bytes, any ObjectDB memory, still allocates a lot of ...

 
api-jdo

makePersistentAll(pcs)

Make an array of instances persistent.(Method of javax.jdo.PersistenceManager)

 
api-jpa

lock(entity, lockMode, properties)

Lock an entity instance that is contained in the persistence context with the specified lock mode type and with specified properties.(Method of javax.persistence.EntityManager)