About entity

forum_thread

Garbage Free Persistence?

Hi, I am trying to make my application garbage free. I noticed ObjectDB is not garbage free - I noticed that by persisting the same object 1mio times - and I can see the java garbage collector kicking and the usedHeap increasing. Is there a way to persist entities in a garbage free manner? Thanks EKK #1 2016-08-09 10:31 Hi, I am trying to make my application garbage free. I noticed ObjectDB is not garbage free - I n ...

 
issue

UnexpectedException on query

Hi, I'm getting the following exception when trying to query an Entity type by id using googlecode generic dao.   ... getting the following exception when trying to query an Entity type by id using googlecode generic dao.   [ObjectDB ... is as followed: SELECT _it_ . id FROM my_entity _it_ WHERE _it_ . id = ? and the queried id exists in ...

 
forum_thread

Managing software release cycles.

How do you manage software release cycles with objectDB? For example we might have different installation of a given web application, and we might need to introduce new fields with default values or to change something in the database "structure".  How can we apply the update script without downloading the entire DB file? Are there any command line tools like sqlPlus to connect to a DB and execute queries / scripts? ... You can simply add new fields to an existing entity class and they will have default values. > or to change ...

 
forum_thread

Is there any faster select method?

SELECT: TypedQuery<Point> query = em.createQuery("SELECT p FROM Point p WHERE p.id = " + element.getId(), Point.class); List<Point> points = query.getResultList();   WRITE: em.persist(p);   ** the Point class is of the tutorial.   I found the above select method is ten times slower than the write method, in my very simple benchmark. I guess the reason there is no SQL in the write method.   ... 2011-02-19 21:53 Entity objects can be retrieved by their primary key (object ID) directly using ...

 
tutorial

Step 3: Define an EJB Session Bean

Explains how to define an EJB session bean in an Eclipse Java EE 6 web application.... methods: persist - for storing a new Guest entity object in the database. getAllGuests - for retrieving all the ...

 
forum_thread

Level 2 cache not hit in @ManyToOne

Hi! I have 2 entities: User and Item, both @Cacheable. Item has @ManyToOne private User user. Level 2 JPA cache is activated and it works ok for find by id (tested by changing data in explorer and reading in my app). Problem 1: find by id on Item it's good, it hits the cache, but not for its field "user". "user" is loaded each time from the DB (tested by changing data in explorer and reading in my app). "user" should also be taken from L2 cache, shouldn't it? Otherwise...it's a huge performance hit. #1 2013-07-26 10:56 Hi! I have 2 entities: User and Item, both @Cacheable. Item has @ManyToOne private User user. Level 2 JPA ...

 
api-jpa

JoinTable.name

(Optional) The name of the join table.(Annotation Element of javax.persistence.JoinTable)

 
api-jpa

javax.persistence.PostRemove

Is used to specify callback methods for the corresponding lifecycle event.(Annotation of JPA)

 
api-jpa

javax.persistence.NamedQuery

Specifies a static, named query in the Java Persistence query language.(Annotation of JPA)

 
api-jpa

SecondaryTables.value

(Required) The secondary tables for an entity.(Annotation Element of javax.persistence.SecondaryTables)