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Query in JPA2 with LEFT JOIN on INNER JOIN

select a.description, a.id, p1.description, p2.description,p3.description from action a left join action_profile ap1 on ap1.id_action=a.id inner join profile p1 on  ap1.id_profile=p1.id  and p1.name='?' left join action_profile ap2 on ap2.id_action=a.id inner join profile p2 on  ap2.id_profile=p2.id  and p2.name='?' where a.id =?;   Thanks   ... Sorry, but I use Criteria API. edit ...


Indexing a field results in internal Exception

I have an application that I have been converting from JPA/MySQL to JDO/ObjectDB and I have hit a problem with indexing. An index on a String field is required to give good performance but if I add the @Index annotation to the field I eventually end up with an ObjectDB internal exception.  This is reproducible, as is the program running to completion (slowly) if I remove the @Index annotation.  Is there anything I can look for that might result in this exception? ... I have long been a fan of JDO as it's a hugely easer API and gets work done with a lot less metadata.  ...


Spring LTW Problem

Hello! I use ObjectDB with Spring. Today i tried to swich from AspectJ compile time weaving to load time weaving. (To get Jrebel working properly) So i added  ... since annotations are checked using the Java reflection API - the check itself involves class loading. The stack trace ...


Issue with DISTINCT Select

It is getting more and more frustrating :( We've introduced distinct select instead of regular selection in our code (no changes else) and suddenly receive invalid identifiers in queries exceptions in various queries. Here's the stacktrace: ... = class com . quasado . foundation . contact . api . model . individual . IndividualContact ) ) ORDER ...


Replicated cluster recovery

If I create a replicated database cluster as per http://www.objectdb.com/java/jpa/tool/replication what is the behaviour of the master database after a failure? For example, say I have MasterDB and SlaveDB in the cluster. If MasterDB goes offline the application will automatically switch to SlaveDB. When MasterDB comes back online it will have missed any activity that occured during the downtime. ... cluter it works fine. I had similar situation in JPA API but it was corrected: http://www.objectdb.com/database/support/151 ...


Server vs embedded mode in multi-instance scenario

We are creating a web app that will have multiple different clients, each on their own EC2 instance(s). The clients do not need to share any data, so each could have its own ObjectDB. Clients have a user base of about 2,000 to 60,000 users that could possibly be using their application at any given time (100k absolute maximum). We will probably have multiple instances per client for availability concerns as well as auto scale during peak usage, at least for the benefit of our web application if not for objectdb.... when possible. But since both modes share the same API, you can easily check and compare both with your application. There ...


Criteria query error: Unexpected query token

Using JPA2, I can save entities now in JBoss, and also fetch them uniquely by id. However, if I try to fetch it by getting back all instances (e.g. findAll, I get the following error:   ... be valid in Hibernate HQL but not in JPQL and JPA Criteria API. ObjectDB Support ObjectDB - Fast Object ...


auto-generated uuid fields

Hello, we're porting a JDO application to ObjectDB which uses uuid-hex generated values. However the page on generated values in your JPA tutorial only mentions numeric generated values, and when we try to use it the error message seems to imply that auto-generating strings isn't supported. Could you confirm whether this is the case? If so it seems an odd omission, given that it's part of both the JPA and JDO standards (JPA Generator.UUID_HEX and JDO value-strategy="uuid-hex") and that the Java language itself supports it (java.util.UUID). ... your documentation page at http://www.objectdb.com/api/java/jdo/annotations/IdGeneratorStrategy which lists the UUIDHEX and ...


Custom Classloader: Issues with the Enhancer Agent

In my use case I generate some classes dynamically and load them with a custom classloader. The classloader is very standard and does something like this (simplified): ... for enhancement is done  using the Java reflection API, so the class has to be loaded before enhancement. Because of possible ...



This interface is implemented by a non-binary-compatible JDO implementation to provide state interrogation for non-enhanced persistent classes.(Interface of JDO)