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... method finding problems. Fixed a bug in the results of IS [NOT] NULL queries. Fixed a bug in ObjectDB ...


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: ... priority="40" />   <query-cache results="1024mb" programs="500" />   <extensions drop="temp,tmp" ...


CASE WHEN...THEN...ELSE...END not working using JPQL/JDOQL

When I try to use the "case...when...then...else...end" like in the following query "SELECTCASE WHEN g.name="a" THEN "e" ELSE "o" END g from Guest g", I get the issue: Unexpected query token 'CASE' SELECT  ==> CASE <==  WHEN g.name="a" THEN "e" ELSE "o" END g from Guest g Have I mismatched something or is it an issue with ObjectDB? Anyone could help me on how to use the "case" in JPQL? Thank you in advance. ... query with a simple SELECT g and then adjusting the results in a Java code loop. ObjectDB Support ...


Bidirectional OneToMany is slow on updated items

Hello, I have a problem with the following situation. I insert persons with addresses. In the first run, they are all new with a new address. It runs fast. In the second run, the persons are all loaded and got a second address. This seams to be much slower. The Entities are all enhanced by the javaagent (which you can see in the contained eclipse launch configuration) Is there any way to speed it up?       ... this mapped by collection to an ordinary collection, the results are: ...


Login Error (bad username 'admin' or password)

I am getting following error when i am trying to connect to server: [com.objectdb.o._PersistenceException: Login Error (bad username 'admin' or password)] with root cause com.objectdb.o.UserException: Login Error (bad username 'admin' or password) at com.objectdb.o.MSG.d(MSG.java:61) at com.objectdb.o.HND.K(HND.java:210) at com.objectdb.o.SHN.K(SHN.java:208) at com.objectdb.o.HND.run(HND.java:132) at java.lang.Thread.run(Thread.java:662) Here is my connection string: #1 2013-03-31 01:41 I am getting following error when i am trying to connect to server: [com.objectdb.o._PersistenceException: ...


ObjectDB Web Site - Terms and Conditions of Use

... make any representations concerning the accuracy, likely results, or reliability of the use of the materials on its Internet web site or ...


Multithreading Test and Deadlock

I move on to testing the multi threaded part of ObjectDB. From the same code (MyMain.java), I set the thread count from 1 to 4 and not only do I found it's slower overall (each thread only needs to insert 250K entities) but the threads are stuck with a deadlock. All threads share the same EntityManagerFactory but they have their own EntityManager. The stack trace is attached. ... brings 1-thread and 4-threads runs to equivalent results, so maybe in this test 4 threads are slower because of higher memory ...



This interface is the point of contact between managed instances of PersistenceCapable classes and the JDO implementation.(Interface of JDO)


java.lang.ClassCastException: com.objectdb.o.RFV cannot be cast to com.objectdb.o.RSV

The following query: SELECT count(m) FROM Message m WHERE m.attachments.original=:template is generating this exception: Bug Version: 2.5.2 Priority: High Status: Fixed Replies: 2 Type:  Bug ...


Query to search for common elements in two separate collections.

I'm trying to work out the most efficient way to build a query that can compare two collections for identical members. Something like: "SELECT o FROM Object o WHERE o.someCollection CONTAINS MEMBER OF :someCollection" Is something like this possible in the JPA spec? ... by iteration of the smaller sized collection retrieving results for matches that contain the element for each iteration until all have ...