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Thrown by the persistence provider when a problem occurs.(Exception of JPA)


Cascading persistence through an inverse field

Hi! I was playing with cascading persistence with @ManyToMany and inverse @ManyToMany fields, and I noticed that I can only get cascading persistence in one direction. If the "owner" of the relationship is persistent, then objects that are added to the relationship are automatically made persistent. However, I can not get this to work the other way around. I would also like the relationship owner to be persisted if a persisted object is added on the owner side. I have included a minimal example: ... ) private Set<Point> points = new HashSet<> ( ) ;   public void ... Scenario 1: PointCollection col = new PointCollection ( ) ; em. persist ( col ) ...


Does ObjectDB support lazy loading?

I'm evaluating ObjectDB 2.0 RC1. Everything works fine except a lazy loading problem. I've a Parent class which contains List<Child>, marked with @OneToMany. After persisting a Parent object, (in the Explorer) I can see all the property values of the Child objects in the list. However, when the Parent object is read from EntityManager, all the properties except ID of the Child objects are null. The EntityManager is not yet closed when the getters are called.... . begin ( ) ; A a = new A ( ) ; a. list = new ArrayList<B> ( ) ; a. list . add ( new B ( 1 ) ) ; a. list . add ( ...


Issues with JDO Casting & Full Qualified Names

hi! See this query and the comments about failures. This is really urgent for us because as you've stated, this is the only workaround for now to proper casting AND map KEY access though it isn't working correctly either.. ... ( ) ; MyEntity entity = new MyEntity ( ) ; entity . embeddeds . put ( "test" , new EmbeddedA ( ) ) ; entity . embeddeds . ...


Object explorer cannot open odb file. ObjectDB many-to-many relationship

I created a data model to test many-to-many relationship with a link table as following (full code in attachement) ... ( ) ;   User u1 = new User ( "u1" ) ; User u2 = new User ( "u2" ) ; Project p1 = new Project ...



The Throwable class is the superclass of all errors and exceptions in the Java language.(Class of java.langClass Throwable)



This class represents exceptions caused by the use of optional features not supported by the JDO implementation.(Exception of JDO)



This class represents exceptions caused by an attempt to update a datastore when the PMF was created as "read-only".(Exception of JDO)


Empty temporary dat files in the temp folder

Hello, We have questions regarding the pagesX.dat files in the temp directory. We detected a problem on a machine with ‘only’ 2GB free memory on disc drive C:/ because during using our Product the %temp%/objectdb_123... folder growth up to 2GB. And then we run into some following errors due to lack of memory. ... entities from one of the additional DB’s we get five new pagesX.dat files (each 8MB) in the TEMP directory. If we take a look into ... objectdb.temp.page-file is enabled (as part of the new experimental feature of supporting very large transactions, as requested ...


Queries are slow on a large database

Hi, I have a 12GB database with 787603 entries. It is much larger than usual and there are performances issues. I am doing small queries and they take much longer than I expect, i.e.: Get the total number of entries Get 25 consecutive entries (i.e. 0-25) Get one specific entry On average each query needs 4 to 5 minutes to return a result. I have been adviced to use indexes but they are already used through the JDO Metadata file. For instance I use this class: ... the index rather than by accessing the data. If you add a new index to an existing database use the Doctor to create a new database in which the index is active. If this doesn't help ...