About persist


How to use JOIN FETCH?

The ObjectDB manual (http://www.objectdb.com/java/jpa/query/jpql/from) gives an example of using JOIN FETCH to avoid excessive round trips to the database: ... "20000101" ) ,address1 ) ; em. persist ( address1 ) ; Address address2 = new ... "20100101" ) ,address2 ) ; em. persist ( address2 ) ; em. persist ( p ) ; ...


Left join fetch behaviour doesn't retrieve children?

Hello support, I'm a little bit confused about a left join fetch behaviour. In this test case, i try to fetch my 3 children using a left join fetch. But my collection is null after closing the em. It was expected to be fetched before closing the em, no ? In fact, that is the objective of the fetch purpose (i guess ?). ... combinaison + various cascade combinaison + merge / persist parents and childs + add indexes ) to bere sure all is fine no matter ...


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"> ... ( "hello" ) ) ; em. persist ( holder ) ; em. getTransaction ( ... ( cascade = CascadeType . PERSIST , fetch = FetchType . EAGER ) public ...


Run out of memory

Hi, I've been looking into ObjectDB for our use, where everything has been great apart from I'm stuck on the following problem.   I am trying to load a large file (> 1GB), process certain information and store it back in the database to access / modify later. I require to be able to rollback changes as well, where there can be massive amount of changes.   ... calling flush followed by clear the uncommitted changes persist in RAM (not the file db), hence I am getting out of memory exceptions. ... data ) { this . em . persist ( data ) ; if ( this . commitCount ...


Entity Management Config questions

Hi, the manual states the following regarding config of Entities: http://www.objectdb.com/java/jpa/setting/entities  : <cache ref="weak" level2="0mb" /> The <cache> element specifies settings of the two cache mechanisms for entities: #1 2010-12-20 07:36 Hi, the manual states the following regarding config of Entities: http://www.objectdb.com/java/jpa/setting/ent ...



This interface is the point of contact between managed instances of PersistenceCapable classes and the JDO implementation.(Interface of JDO)



Return the persistence type.(Method of javax.persistence.metamodel.Type)



Specifies a persistent field or property of an entity whose value is an instance of an embeddable class.(Annotation of JPA)



Utility interface between the application and the persistence provider managing the persistence unit.(Interface of JPA)


Wrong data stored in time only fields

This may be related to the fix for the problem described in this thread: Wrong data stored in date only fields. The object and its date and time fields are the same as in the referenced thread. Except we are using ObjectDB 2.6.4_08, the system time zone is set to EST and both the OS and JVM are using the 2015g time zone data. ... 18:18:14" ) ) ; em. persist ( dt ) ; } catch ( ... 21:26:19" ) ) ; em. persist ( dt ) ; } catch ( ...