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Compare old and new schema

Hello, I have an old database file with important data. Over time, I have modified some of the entity classes but did not keep track of the changes. Some fields may have been renamed or removed, some classes may have been renamed or changed package. Is there a way for me to check what "format" the entity classes have in the old database file and compare that with the new classes definitions?   Thanks, farid ... With this in mind, I created a separate project where I opened an EntityManager on a copy of the database file. I can now use a ...

 
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Memory consumption of empty Strings

After doing some memory related research in my program, I found a possible place for an enhancement of objectdb: My program has several entities which contain many String. Often some of these String are empty (""). To avoid unnecessary memory consumption, the String within the entities are initialized like: String firstName = ""; ... one further possible enhancement: implement a setting, where the developer can specify which Strings should be loaded via the ...

 
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server.exe on 32bit and 64bit Windows

Is the server.exe compatible to start the objectdb server on Windows 64bit OS?  Or 32bit only?   ... files (in the directory of explorer.exe and server.exe), where each file has a single text line: vm.location=C:\Program ...

 
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TreeSet and compareTo() issue

Hi I'm trying to use TreeSet but getting NPE on the compareTo() method when it does a find(): ... the test app is self-explanatory...I've commented where the NPE occurs.  It's probably something stupid that I'm ...

 
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Sample JDO Architecture for Follow Up Questions

I am trying to finalize on my application's JDO and ObjectDB archieture.  I have done documentation survey (reading JDO books, studying ObjectDB's documents and forum) and have designed what I think is the best architecture for my particular application usage model. ... about this proposed architecture:   "Where Does ObjectDB Block/Lock?" "How Should I Configure objectdb.conf to ...

 
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Compile time enhancement using build.xml of a Netbeans web application

Does anybody have a complete, working example of the adaptations required in the build.xml of a Netbeans web application project to specify ObjectDB compile time enhancement, for both single file and whole project compilation ? The ObjectDB 2.3 manual gives the following tip: ... enhancer" /> </target > (Where obviously the path to your objectdb.jar has to be adapted.) ...

 
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Drop the entire database, Change the schema

I am trying to port and example app to ObjectDb. As part of the tests I drop the database and reload it with the new schema automatically between test cycles. Is there a simple way to do this with ObjectDb, or is the only way to delete the database file everytime? Thanks ... 2011-10-07 21:07 where in the configuration file does this go?   ...

 
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Optimistic lock failed

Hi, I frequently see exceptions during development such as com.objectdb.o._RollbackException: Failed to commit transaction: Optimistic lock failed for object com.example.MyEntity#3 (object has version 1 instead of 3) Could you please explain what this means, and what I can do about it. Thanks you, Carl     ... or you've got some super wierd situation where that causes a signifcant performance issue.If you can't use ...

 
manual

Running JPA Queries

Explains how to use JPA to run Java Persistence Query Language (JPQL) queries.... Page... ( "SELECT c FROM Country c WHERE c.name = 'Canada'" ) ; Country c = ( Country ...

 
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Grouping by date()

Hi, For some time now we can use date and time function in queries to extract part of date time (from documentation): YEAR({d '2011-12-31'}) is evaluated to 2011. MONTH({d '2011-12-31'}) is evaluated to 12. DAY({d '2011-12-31'}) is evaluated to 31. HOUR({t '23:59:00'}) is evaluated to 23. MINUTE({t '23:59:00'}) is evaluated to 59. SECOND({t '23:59:00'}) is evaluated to 0. ... BY hour ( ov . created ) ASC where ov.created is normal Date() field return only hours from 0 to 11 (check ...