About SECOND

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? ... are sufficient. For a special use case, we now use a second database. Within the real transaction we work with a copy of this database. This enables us to repeatedly commit on the second database and in case of a fault we can still recover a consistent ...

 
manual

Index Definition

Describes how to define indexes in JPA entity classes and explains how indexes are used in JPQL queries.... p . y BETWEEN 50 AND 80 For the second query above, the index order should be x first and y second. Indexes on collections are useful in JOIN queries: SELECT ...

 
manual

JPA / JDO Class Enhancer

The Enhancer is a post compilation tool that improves performance by modifying the byte code of compiled classes after compilation.... for loading classes for enhancement can be specified as a second argument: com. objectdb . Enhancer . enhance ( ... it only works on Sun JDK 6 (and not on JRE 6 for example). Second, classes that are loaded into the JVM before accessing ObjectDB cannot ...

 
forum_thread

EntityManager JPA or JDO impl and different behavior

Hi, I have an issue with the EntityManager. My persistance XML looks like: <?xml version="1.0" encoding="UTF-8"?> <persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"> ... it all fails horribly. Have a look at the output from the second junit test, you will see heaps of calls like: AttributeName ... to look only at the database id.   Second issue. The docs at: http://www.objectdb.com/api/java/jpa/OneToMany ...

 
issue

Read only hint for query

Second thing after @FetchGroup I've found is read-only hint for EM. You can specify this hint to EM when executing query meaning that returned data will never be edited or persisted. My understanding of this is that each entity returned from query is in detached state as default state. query.setHint("odb.read-only", "true"); This could be useful in situation when you are sure, that you won't modify those entities - like listing entities, paging, logging, reporting. ... 2013-01-21 13:00 Second thing after @FetchGroup I've found is read-only hint for EM. You can ...

 
forum_thread

Replication not working anymore

Hello! I upgraded my ODB Version to 2.5.4 to get rid of some bugs. Now i tried to start my replica server. It starts fine and then crashes after a few seconds with the following exception: #1 2014-01-10 15:39 Hello! I upgraded my ODB Version to 2.5.4 to get rid of some bugs. Now i tried to start my replica server ...

 
api-jpa

ge(x, y)

Create a predicate for testing whether the first argument is greater than or equal to the second.(Method of javax.persistence.criteria.CriteriaBuilder)

 
forum_thread

Unable to run NetBeans/JPA Web Application Tutorial

I followed each and every step of NetBeans/JPA Web Application Tutorial but when i am trying to the web application the following error is prompted on the run console: Start is in progress... start?path=/GuestBook FAIL - Application at context path /GuestBook could not be started C:\GuestBook\nbproject\build-impl.xml:1050: The module has not been deployed. See the server log for details. BUILD FAILED (total time: 2 minutes 13 seconds)   #1 2014-04-26 17:53 I followed each and every step of NetBeans/JPA Web Application Tutorial but when i am trying to run the web appli ...

 
forum_thread

Attempt to execute a query using a closed EntityManager

Hi again! Suddenly, my app started to throw this exception. I would really appreciate some advices. ... @Stateless ClientC.create(and passes the user) 4. Second: LOG.log(Level.INFO, "Created client {0}", c.getId()); Here is when ...

 
forum_thread

Problems with Tutorials » JPA Web App (Tomcat) » NetBeans JPA Web App

I made all the tutorial about the GuestBook but at the end, though it build correctly, when trying to run it, I got: C:\...\NetBeansProjects\JavaWebAppODB\nbproject\build-impl.xml:686: The module has not been deployed. BUILD FAILED (total time: 0 seconds) Can any body please help me with this error? It seems I've done everything correctly, but I still don´t know how to solve the problem, cheers, and thank you in advance,   Alan #1 2011-04-22 20:05 I made all the tutorial about the GuestBook but at the end, though it build correctly, when trying to run it, I g ...