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forum_thread

Updating existing persistence entries

I have stored some instances of MyObject via em.persist(myObjectInstance); I can fetch them and bind them to a kind of property editor in my app (it simply calls the setters to reflect gui editing actions). When I try to persist a object later on, I get an error like com.objectdb.o.UserException: Attempt to reuse an existing primary key value which makes sense to me but I'm missing a em.update() method. #1 2012-12-07 19:29 I have stored some instances of MyObject via em.persist(myObjectInstance); I can fetch them and bind them ...

 
issue

Sometimes the ObjectDB throws an internal expeption if a persist() was executed

[ObjectDB 2.6.6_08] Unexpected exception (Error 990) Generated by Java HotSpot(TM) 64-Bit Server VM 1.8.0_51 (on Windows 7 6.1). Please report this error on http://www.objectdb.com/database/issue/new com.objectdb.o.InternalException: java.lang.NullPointerException: null java.lang.NullPointerException at com.objectdb.o.OBM.bE(OBM.java:395) at com.objectdb.o.OBM.bE(OBM.java:269) at com.objectdb.jpa.EMImpl.persist(EMImpl.java:442) Bug Version: 1.04 Priority: Low Status: Closed Replies: 7 Type:  Bug ...

 
manual

SELECT clause (JPQL / Criteria API)

Explains how to use the SELECT clause and projections in a JPA/JPQL query. The ability to retrieve managed entity objects is a major advantage of JPQL. For example, the following query returns Country objects that become managed by the EntityManager javax.persistence.EntityManager JPA interface Inte ...

 
forum_thread

Running ObjectDB on a node that does not have internet connectivity

Upon initializing our ObjectDB database on a node that does not have a connection to the outside internet, we get the following exception. Any idea what would be causing this?... happen if the XML headers of the package.jdo files do not match the local dtd. Try to set the headers of all your package.jdo files ...

 
forum_thread

Restrict by class in query

I have the following bit of code: ... has to be thrown if the specified result type doesn't match the query string, but currently ObjectDB silently ignores such a ...

 
manual

JPA Lifecycle Events

Explains how to use JPA lifecycle events (client side triggers) with callback methods and listener classes. Callback methods are user defined methods that are attached to entity lifecycle events and are invoked automatically by JPA when these events occur. This page covers the following topics: Internal Callback Methods ...

 
forum_thread

Is it possible to commit only specific elements?

Hello, As stated above, I would like to know if it is possible to commit only specific elements, or at least update a single table, disregarding the other entities loaded in the persistency context? I have a complex hierarchy of intertwined objects. Currently I am clearing my persistency context, retrieving only the needed ones, creating new ones (which I want to commit), detaching the ones I've previously retrieved and finally committing. My context is big data and performance is an issue.      #1 2015-07-24 11:13 Hello, As stated above, I would like to know if it is possible to commit only specific elements, or at le ...

 
api-jpa

javax.persistence.LockModeType

Lock modes can be specified by means of passing a LockModeType argument to one of the javax.persistence.EntityManager methods that take locks (lock, find, or refresh) or to the Query.setLockMode() or TypedQuery.setLockMode() method.(Enum of JPA)

 
forum_thread

@ElementCollection query returning extra result per element in collection

Hi, ... return the same company with different branches that match the filter. Similarly, selection of only companies may return duplicate ...

 
forum_thread

Embedded & Activation & Scalation

Hi there, Our app is highly scalable and can be distributed among multiple processes on multiple machines. ObjectDB Server is not really scalable right now and would be a SPOF for our application. So, we'd like to embedded odb into each instance instead for now and point each to the same database folder, however I've got a few questions I couldn't find answers for: #1 2012-01-30 07:39 Hi there, Our app is highly scalable and can be distributed among multiple processes on multiple machines ...