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Numbers in JPQL and Criteria Queries

Shows how numbers, arithmetic expressions and numeric functions and operators (MOD, ABS) can be used in JPQL queries.... by JPA: 2 unary operators:   + (plus) and - (minus). 4 binary operators:   + ...



A "RegisterClassEvent" event gets fired whenever a persistence-capable class is loaded and gets registered with the JDOImplHelper.(Interface of JDO)



This method gets called when a persistence-capable class is registered.(Method of javax.jdo.spi.RegisterClassListener)


Entity Version History

ObjectDB manages automatic entity versioning (for optimistic lock purposes). Every entity object modification is reflected by a new version number. Previous values in the entity object that are overridden by new values, however, are discarded. Some applications may benefit from the ability to go back in time and view old versions (and old values) of entity object. Future versions of ObjectDB should support archiving old versions of specific entity classes.... to avoid the $5000 MySQL Enterprise license which is a plus! edit ...


Activated ObjectDB still throws "Too many persistable types"

I have upgraded from 2.3.7 to 2.4.4 and now my activation won't work, throwing the dreaded com.objectdb.o.UserException: Too many persistable types (>10) - exceeds evaluation limit I have already reactivated and checked that my objectdb.conf is correctly used (by inserting random chars at the beginning of the file, which lead to an error). Yet I still get the error thrown. Nothing in my configuration changed except the version. What could possibly be the problem with that? ... it is running on the server, using the standard settings (plus the activation code). As I outlined, the correct configuration file is ...


@ElementCollection Set<Integer> is emptied sometimes

Hi! I'm facing a really strange behavior, which I can't yet reproduce, but it happened 3-4 times already. ObjectDB seems to clear some fields that are @ElementCollection Set<Integer> of my objects. They appear HashSet<Integer> in ObjectDB Explorer. The only common thing I've seen is that this MAY happen when schema changes, even though nothing is changed in that Object's class. Any ideas why would this happen and how could it be avoided? Thanks (version 2.5.3 & Tomee & NetBeans) ... have attached the class that does that, a @Singleton EJB, plus the affected entity. ...


PersistenceException: Failed to locate field

Hi, have recently been running into this issue when changing the schema: com.objectdb.o._PersistenceException: Failed to locate field in this case, adding a primitive String field to an Entity. pretty sure that in the past schema evolution would not have triggered errors, is this case, a simple new field, shouldn't the policy be to add a null in that field, or other default for that primitive. ... useful to log the location of the config file it is using, plus the contents of that config file, given that I've found many cases ...


ClassCastException of same object type

I have ObjectDB partially working with my project. At the moment it seems to be saving objects and retrieving objects ok in the main project. However, when I make a plugin for the project, the new objects are persisted but not retrieved. I get the following error: java.lang.ClassCastException: org.sportscoring.ssv.xc.core.XCCompetitorCount cannot be cast to org.sportscoring.ssv.xc.core.XCCompetitorCount ... objectdb from the supplementary plugin to the main plugin plus a few fixes allowed the application to work. Transferring the classes back ...