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forum_thread

java.lang.ClassCastException in OSGi runtime when loading data from DB

Hello, I'm trying to use ObjectDB in an OSGi environment (Karaf 4.0.7). I'm now facing ClassCastExceptions on my "entity" classes when I try to read data from the DB. In a very old (2011?) forum entry this problem was already discussed and it appears to be related to classloader problems. My entity is a dedicated bundle. I have one bundle with the database service (doing the actual objectdb actions -> persist, query etc). #1 2016-12-09 10:44 Hello, I'm trying to use ObjectDB in an OSGi environment (Karaf 4.0.7). I'm now facing Cl ...

 
release

2.3.4

Release date: 2011-11-25 Download (5.49 MB) Binary:  objectdb-2.3.4.zip You should start by following a  tutorial or reading the manual ...

 
release

2.3.5

Release date: 2011-12-21 Download (5.38 MB) Binary:  objectdb-2.3.5.zip You should start by following a  tutorial or reading the manual ...

 
forum_thread

Searching lists within objects

Hi everyone,  I've a problem with searching on lists. I'm uncertain as to what the best form is, so I've created a maven project with all the classes and a unit test showing my issue. Pretty much I want to search using cb.isMember passing an object. This however does NOT work. I'm uncertain how the database is doing its matching, but it looks to me like it matches using objectids, which means you can only match isMember if you have a database object. This does not help as I'm never going to have the real object at search time. #1 2011-07-07 00:59 Hi everyone,  I've a problem with searching on lists. I'm uncertain as to what the best form ...

 
manual

[ODB1] Chapter 7 - JDOQL Queries

Explains how to use JDOQL, the Java/JDO Query Language. There are various ways to retrieve objects from an ObjectDB database, as shown in section 6.3 . An Extent , for instance, can be used to retrieve all the instances of a specified persistent class. When a more selective retrieval is needed, JDOQ ...

 
manual

[ODB1] Chapter 5 - JDO Connections

The PersistenShows how to use database connections and transactions in JDO. ceManagerFactory interface represents a factory of database connections. Its main role is to provide PersistenceManager instances. The PersistenceManager interface represents a database connection. Every operation on a database requires a PersistenceManager instance. The Transaction interface represents a transaction on a database. Every operation that modifies the content of the database requires an active transaction.[toc hidden:1] This chapter describes three essential interfaces for using JDO: 5.1  javax.jdo.PersistenceManagerFactory 5.2  javax.jdo.PersistenceManager 5.3  javax.jdo.Transaction The PersistenceManagerFactory ...

 
forum_thread

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   #1 2013-01-23 13:29 How write a query in JPA2 with LEFT JOIN on INNER JOIN? SELECT a . description , a . id , p1 ...

 
release

2.3.3

Release date: 2011-11-10 Download (5.49 MB) Binary:  objectdb-2.3.3.zip You should start by following a  tutorial or reading the manual ...

 
forum_thread

Performance tuning, best practices

we have a system where we serve from a host process around 200 clients connected via webSockets (Jetty). The core process is running on a dedicated Windows 2012 server with 16 GByte RAM and 8 processor cores.  What is strange for us is that max 20% of the cpu resources are used and the IO subsystem is at maximum 30% of activity under heavy load but database queries are let's say not at the speed we would expect. We have currently 20.000.000 objects in the database, our configuration settings are: #1 2016-11-15 08:07 we have a system where we serve from a host process around 200 clients connected via webSockets (Jetty). The core ...

 
release

2.3.6

Release date: 2012-01-09 Download (5.38 MB) Binary:  objectdb-2.3.6.zip You should start by following a  tutorial or reading the manual ...