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Fetching Collections Puzzle

I am working on a project where I need to travel through a massive graph of objects. One of the main entity is the Node which is shown below. class Node { Node parent List<Node> children Node rightSibling Node leftSibling int rank } I have the following issues/doubts ... that JPA spec if i recall correctly does not specify the number of collections you can fetch through a query but in practice  I ...

 
manual

Storing JPA Entity Objects

Explains how to use JPA to store (persist) entity objects in the database.... ). Batch Store Storing a large number of entity objects requires special consideration. The combination of the ...

 
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Soft Reference Object Cache Recommendation

(Trying again.  Last post, ~50 minutes to compose, failed, possibly due to an attachment upload size limit being exceeded before the post attempt.  =(  ) ... cache="1mb" max-threads="10" />) is a HINT to the number of PAGs that may be created.  I also understand that those PAGs are ... commit?) What I don't understand is that the number of PAGs seems to continue growing well beyond the requested limit.  ...

 
doc

java.lang.RuntimeException

(Exception of java.langException RuntimeException)

 
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lockfiles in client/server mode

i have an objectdb server running on localhost as user "objectdb", spawned like so: java -server -cp /usr/local/share/objectdb/objectdb.jar: com.objectdb.Server -conf /etc/objectdb/objectdb.conf start it has naturally created and taken ownership of /tmp/ObjectDB. #1 2012-04-05 21:36 i have an objectdb server running on localhost as user "objectdb", spawned like so: java -server ...

 
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Removing an entity throws exception

Hi all, I'm testing ObjectDB for my project, but I have troubles with it. At this time I'm not able to remove customer entity, when it's read by a query (it's attached), it throws this exception: Exception in thread "AWT-EventQueue-0" java.lang.RuntimeException: com.objectdb.o._RollbackException: Failed to commit transaction: 51 ... ... Thank you for fast response. The fix changed the number 51 to 34. But it looks like my db was corrupted, because when I tried to ...

 
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Missing Data on Retrieval (0, null values)

I try  to export all Objects in an Flatfile-Hiearchy (.csv). But only the first exported Table contains all necessary Data. Most of the others  contains all  Object-Rows', but most Values of the Columns are missing. With a  em.clear() inside the Loop, all tables are exported correctly but the Enity-Keys do not match. I can't get the point - what am i doing wrong?   emf = Persistence.createEntityManagerFactory(dbFile); em = emf.createEntityManager(); ... or more entity classes, but you may be able to reduce the number of entity classes in your specific project (if it is not very large) by ...

 
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ODB IndexActivation NullPointerException

Hi, We have created indexes on an existing database, which has 4.3 million objects. As soon we create first query, NullPointerException is thrown: ... in the log file as it should contain also the actual build number. If you use client-server mode use the new version on both ...

 
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performance limit

Hi, can someone share expirience with performance limits of ObjectDB especialy when quering tables with large records sets. Our issue is with tables with 100.000+ records. Everything was OK when we had few thousand records. We have a simple SELECT statement which selects from a table with 100.000+ records by UserID atribute, tables have from 5 to 20 atributes. Usualy the results range from few hundred to few thousand records. This query takes up to 12 seconds. Is this normal, what when we will have few milion records, how to handle this. ... If a proper index is defined and in use the effect of the number of candidate objects is minimal. There is probably a good reason for ...

 
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@Transient

Hello, I have a persistent class which looks something like this: @Entity public class Test { private String string; private Date date; @Transient private boolean test; // getters/setters } When I persist the class the transient 'boolean test' is stored in the database, maybe I am doing it wrong but I expect #1 2010-11-22 12:16 Hello, I have a persistent class which looks something like this: @ Entity public ...