About fetch


Query results are not up to date for entities, not primitives

When using the CriteriaBuilder to query, the retrieved list are not refreshed according to the latest updates. But, when using the JPQL Query, the list are refreshed. What is the problem? ... ref = "strong" level2 = "0mb" / > <fetch hollow = "false" / > <persist serialization = ...


Setting and Tuning of JPA Queries

Explains various JPA query settings - result range, flush and lock.... JPA code by ObjectDB. "objectdb.result-fetch" - sets fetch mode for query result as either "EAGER" (the default) or "LAZY" . ...



This class is a helper class for JDO implementations.(Class of JDO)


Saving custom list which implements java.util.List fails

Hi, I'm evaluating ObjectDB for storing Objects modeled with Eclipse Modeling Framework (EMF) and encountered the following problem:   I took the Point-example from the tutorial and added a list-attribute which is declared as java.util.List but the actual Object MyList just extends ArrayList as shown below. #1 2013-03-27 13:39 Hi, I'm evaluating ObjectDB for storing Objects modeled with Eclipse Modeling Framework (EMF) ...


performance limit

Hi, can someone share expirience with performance limits of ObjectDB especialy when quering tables with large records sets. Our issue is with tables with 100.000+ records. Everything was OK when we had few thousand records. We have a simple SELECT statement which selects from a table with 100.000+ records by UserID atribute, tables have from 5 to 20 atributes. Usualy the results range from few hundred to few thousand records. This query takes up to 12 seconds. Is this normal, what when we will have few milion records, how to handle this. ... with lazy result loading, using the objectdb.result-fetch query's hint in order to separate query execution from result ... Loading the query results could be very slow if eager fetch is used extensively, and then your 6500 result objects may require ...


find() delay

Hi, I tried objectdb in following steps: 1, for 1 to 30 {trans.begin(); create typeC o; em.persist(o); trans.commit();} 2, for 1 to 30 {p = em.find(typeC.class, i); print(p)} So simple a test, there is no result in one go; I have to disable step 1 and run again, then Step 2 output the expected results. I tried em.flush(), em.clear(), etc.. that do not work. Any idea? TIA ... OneToMany ( mappedBy = "parent" , fetch = FetchType . EAGER ) protected ...


Object DB vs EclipseLink/TopLink: Unloaded relationships in detached entities

This topic is for those considering migrating from EclipseLink JPA or TopLink to ObjectDB JPA. ... until the stateful bean is released. 3. Use a FETCH JOIN as described here: Detach JPA objects with lazy ...


JDO sequences from ORM file

I want to use sequences in JDO without using annotations. Normally this is done with a package-X.orm file, where X is a value passed to the PersistenceManagerFactory as the value of property "mapping". I'm encouraged to see that the JDO zip that comes with ObjectDB includes the DTD/XSD for this type of file, though I can't see a mention of it in the manual. ... >   <!-- Persistable Types with Fetch Groups --> <class name = "JdoTypes$ClassWithFetchGroup" > <fetch-group name = "fg1" post-load = "false" > ...


Conflicting modifiers .... (javax.persistence.Id, javax.persistence.ManyToOne)

I have two classes a Container type class and another class that is 'contained' by that class. The contained class, CompoundKeyMapItem, represents an alternate implementation of an object held in a Map, and uses a Compound Primary Key. The contained class therefore uses an @IdClass. This all works fine on Eclipselink. However when I try and run this in ObjectDb I get the following error; ... }   @ ManyToOne ( fetch = FetchType . LAZY ) @ Id private ...


Issue with orphanRemoval and multiple EntityManagers

Hi, We have a problem where our database size grows over time more than expected. We've traced it down to the following issue: ... ( cascade = CascadeType . ALL , fetch = FetchType . EAGER , orphanRemoval = true ) ...