About begin



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...   odb. getTransaction ( ) . begin ( ) ; odb. persist ( agency ) ; ...


Run out of memory

Hi, I've been looking into ObjectDB for our use, where everything has been great apart from I'm stuck on the following problem.   I am trying to load a large file (> 1GB), process certain information and store it back in the database to access / modify later. I require to be able to rollback changes as well, where there can be massive amount of changes.   ... this . em . getTransaction ( ) . begin ( ) ; }   protected void ...



This interface is implemented by a non-binary-compatible JDO implementation to provide state interrogation for non-enhanced persistent classes.(Interface of JDO)


Speed of queries that return many objects

Hi, I have a DB of 146MB - with 1_000_000 elements. Loading the contents (objectDB query in java) takes about 10sec. I am using a recent MacBook (SSD blabla - disk I/O speed is about 400MB/sec - according to blackMagicTest app for mac) - so I was expecting the query to take less than one sec (146/400 = 0.35sec.. + some overhead). I was wondering if this kind of speed is "normal", or if this is something I should investigate. Thanks EKK ... em. getTransaction ( ) . begin ( ) ; for ( int i = 0 ...


JDO PersistenceManager.getSequence() returns null sometimes

When using JDO without annotations, database sequences are normally defined in the ORM file. Following discussion on the forum I was told that ObjectDB supports sequences if specified in the JDO file. Unfortunately, it doesn't seem to be supported consistently. It appears to work only in the situation that a new odb file has just been created AND something has been persisted to it. If nothing has yet been persisted, or if the odb file is not newly created, getSequence() returns null. Code to reproduce: ... pm. currentTransaction ( ) . begin ( ) ; Thing thing = new Thing ( ...


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 = ""; ... entityManager. getTransaction ( ) . begin ( ) ; entityManager. persist ( entity ...



This class can be used by a JDO-aware application to call the JDO behavior of PersistenceCapable instances without declaring them to be PersistenceCapable.(Class of JDO)


Query by array element

Hello, I have a class as follows: @Entity public class MyEntity {     boolean properties[]= new boolean[1024]; } I would like to query objects with feature '42': select me from MyEntity me where me.properties[42]=true Is it possible? Thank you! ...   em. getTransaction ( ) . begin ( ) ; em. persist ( new MyEntity ...


What algorithm in find()

I test the time cost for find(), obtain a linear complexity with the following codes: ... 3 * iBlock ; i ++ ) { trans. begin ( ) ; Node o = new Node ( ) ...


Using a file extension other than .odb

I love that ObjectDB's implementation of Persistence.createEntityManagerFactory(...) treats a parameter ending in .odb as a file name rather than a persistence unit name.  It makes opening a DB in my app as easy as selecting it from a file chooser. However, I wish that I could use a file extension other than odb.  Since this functionality is already non-standard, why not allow it?  Perhaps any string beginning with "file://" could be treated this way. #1 2011-07-28 07:32 I love that ObjectDB's implementation of Persistence.createEntityManagerFactory(...) treats a parameter endin ...