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issue

InternalException during producer/consumer scenario

Hi, I'm trying to use objectdb in a producer/consumer scenario. Producer threads put message objects into a table while consumer threads remove the objects based on age, priority, etc. There are 2 main motivations for using objectdb for this purpose rather than a queue or similar data structure: 1) The consumer can select the "next" object based on a range of potentially complex criteria. 2) The number of objects produced can be potentially exceed available memory so can be held on disk within the objectdb file. ... Error taking message from ObjectDB queue at ...

 
forum_thread

Multi-Threading/Distributed-Database Questions...

Greetings ObjectDB team, All below questions assume a very large database (~1,000,000,000 objects): Q1: In what cases would ObjectDB utilize multi-threading ? how about in JOIN operations ? Q2: Is it true that two read-only JPQL queries accessing the same database file actually run simultaneously if placed into two independent threads ? no I/O synchronization bottlenecks ?... multithreading in this previous thread . References from objects in one database to objects in another database are not supported. ...

 
page

ObjectDB License

ObjectDB Purchase and License info page.... workplace. Servers that are leased or rented from third party web hosting and / or cloud hosting companies (including shared ...

 
forum_thread

Schema-Update: Rename superclass and remove one subclass

Hello, we renamed a superclass and removed one of the subclass. If we then try to open the Database (with ObjectDB-Explorer) we get a "Failed to generate dynamic type ..."   Small Example: Generate Database ... q = em. createQuery ( "SELECT c FROM " + RenamedSuperClass. class . getName ( ) + ...

 
issue

probable error in text of manual about embeddable classes

at http://www.objectdb.com/java/jpa/entity/types website in "Embeddable Classes" section there is a phrase "e.g. their instances cannot be shared by different entity objects" which seems to be wrong. ... share an embeddable object, i.e. include a reference to it from two different entity objects, eventually each entity object will gets its ...

 
forum_thread

ObjectDB Website and Yahoo Mail

The attached image represents the error I got yesterday when I posted my previous reply with "Phew. Thanks a lot..." I thought that you might want to see it. I couldn't upload it yesterday, even though I tried 5 times. The website didn't allow. Moreover, sometimes objectdb's website loads extremely low, between 8-15 seconds for each page. Can you do something to improve it, please? It's a real pain during the day if I want to use it (forum/bugs/docs). Cheers! ... address. This is because currently Yahoo rejects emails from ObjectDB website. No similar problems are known with other mail ...

 
forum_thread

Web Framework Recommendation for leveraging JPA + ObjectDB

Hello dear ObjectDB Community ! First of all let me tell You: I am glad that I have revisited ObjectDB just recently; because with its newly added JPA compliance and affordability, it seems like a natural match to me. I have the following understanding: If I persist standardly against JPA/JDO, I can switch Persistence Engines as I see fit later on ! So that I can easily switch to a true OODBMS like ObjectDB, for instance. ... ! Cheers and Tschüss Kai (Tischler) from Northrhine-Westfalia in Germany In heaven there's no ...

 
tutorial

NetBeans/JPA Spring MVC Web Tutorial

Step by step tutorial that demonstrates how to build a Spring MVC Java web application (with Servlet, JSP and a DAO Bean) in NetBeans using JPA.... Framework) will be downloaded automatically during build from Maven repositories. The Tutorial Steps This tutorial ...

 
issue

Add Type level permissions to ObjectDB Server

It would be useful if instead of creating a web service layer on top of a database, I could just set up permissions to entities and entity variables for client connections. This would be beneficial when providing specific raw data where additional business logic is not required. I suppose you could create transient entities for data that does require additional business logic though. ... ideas and feedback regarding this feature request (also from other ObjectDB users) may help. ObjectDB Support ...

 
forum_thread

How to Use a SF with extended Persistence Context?

Hey, I have a problem to use SF with an Extended Persistence Context Regarding to Transactions. The need for an extended persistence Context emerges for the need to create queries in advance for fast execution so I need to store the queries and I need an EntityManager that doesn't get closed between calls. When I call the SF directly no problem happens but if I use SL to hold a reference to the SF I get com.objectdb.o._PersistenceException: Attempt to begin a new transaction when a transaction is active. ... holds reference to the GuestDao who can now give guests from the DB by their names using findGuest(String name) method. ...