About Data Source

forum_thread

Compress ODB file with XML content

Harman company requested to reduce ODB size as much as possible after database created and one of unliked solution was to use ZIP/UNZIP after/before use object DB database. Harman would like to ask Object Db team about possible internal methods to reduce/compress object DB data on run-time or after close ODB file. Does exist any compress data solution from ObjectDB side? ... possible internal methods to reduce/compress object DB data on run-time or after close ODB file. Does exist any compress data solution ... block. Avoid overflow of published source code examples by breaking long lines . You may mark in ...

 
forum_thread

Level 2 cache not hit in @ManyToOne

Hi! I have 2 entities: User and Item, both @Cacheable. Item has @ManyToOne private User user. Level 2 JPA cache is activated and it works ok for find by id (tested by changing data in explorer and reading in my app). Problem 1: find by id on Item it's good, it hits the cache, but not for its field "user". "user" is loaded each time from the DB (tested by changing data in explorer and reading in my app). "user" should also be taken from L2 cache, shouldn't it? Otherwise...it's a huge performance hit. ... and it works ok for find by id (tested by changing data in explorer and reading in my app). Problem 1: find by id on Item ... block. Avoid overflow of published source code examples by breaking long lines . You may mark in ...

 
forum_thread

Which storage fits best to ObjectDB?

Hi, we are just about to put together a new server for our applications using ObjectDB (v 2.6). We have a dilemma about the storage holding the ObjectDB files: if to invest in a mirrored RAID of SSDs which is clearly the ultimate solution but it quite pricey, or to choose a RAID5/6 of 7200 RPM HDDs. ... of HDDs deliver comparable (but still lower) speeds of data transfer to a single SSD, however only when tested on large media files, ... block. Avoid overflow of published source code examples by breaking long lines . You may mark in ...

 
forum_thread

retrieve without key?

hi, i'm completely new to objectdb. i do have apps running with db4o and perst. i have a db which has only a single model object which would be an entity in objectdb. i'm managing the object in java. i'm loading data from an external source. i use keys from that source. since i have a singleton i want to do something like "get * from entities" knowing there is only one. i've looked at the api and can't see an option to retrieve an object w/o using a key. can this be done? ... i'm managing the object in java. i'm loading data from an external source. i use keys from that source. since i have a singleton i want to ...

 
forum_thread

How to define database structure and insert some initial objects from scratch

Hi from Spain! We're evaluating ObjectDB and we have some questions: - How can we create the initial database structure of our application? We know objectdb is all about objects and probably not need initial structure like tables, but how can we populate some "tables" with initial data from a script? In SQL world we have scripts like "insert into..." - Can we use main objectdb.jar library as jdbc driver for ETL software like Kettle? How about migrating data from another database system? ... tables, but how can we populate some "tables" with initial data from a script ? In SQL world we have scripts like "insert into..." ... block. Avoid overflow of published source code examples by breaking long lines . You may mark in ...

 
issue

TYE NullPointerException

I've been seeing the following stack trace in a couple of tests today: ... objectdb.java.util.ArrayList.__odbBeforeAccess(Unknown Source) at objectdb.java.util.ArrayList.iterator(Unknown Source) at ... 2.3.1_03 should fix the exception (but notice that the data will not be available and the collection would look empty - if it has not ...

 
forum_thread

Schema Update: class hierarchy change

Hello, we try to change the class hierarchy of an Entity. You wrote www.objectdb.com/database/forum/899 that ObjectDB support automatic schema evolution for adding and removing fields and for class hierarchy change.   But our small test failed: At first create a DataBase with one Object of MyEntity ... Source) at ... Source) at sun.reflect.UnsafeFieldAccessorImpl.ensureObj(Unknown Source) at sun.reflect.UnsafeObjectFieldAccessorImpl.set(Unknown Source) at ... Thanks for the Update. Now it works. How can data be saved for modified class hierarchy? Actual it woks to move the ...

 
forum_thread

@MappedSuperclass and @Transient not working as I expected

The problem could be my expectation, since I'm fairly inexperienced with JPA.  But here is the problem: The base class of my entity hierarchy is annotated as @MappedSuperclass, and one of its fields is annotated @Transient.  I expected that when I persist a subclass, no table would be created for the superclass, and the transient field would not appear in any table. The actual result is that there is a table for the superclass.  When I try to examine it in ObjectDB Explorer, it throws a NPE. ... @MappedSuperclass also merely stored schemas, without the data? (I could probably figure this out with a hex editor, but it'd ... block. Avoid overflow of published source code examples by breaking long lines . You may mark in ...

 
forum_thread

Multi-tenant setup

Hi, does anybody have experience with multi tenant setup of objectDB. For example using multiple schema or multiple database. How to handle connections between app (Jboss Wildfly) and pass query request to appropriate database, how to dynamically add new database or schema. There are lot of discussions on how to do it with hibernate Thanks     ... which is the simplicity of representing persisted data using staticially defined POJO classes. A popular alternative approach it ... block. Avoid overflow of published source code examples by breaking long lines . You may mark in ...

 
forum_thread

GWT RPC is throwing serialization exception when I have object db date value

Caused by: com.google.gwt.user.client.rpc.SerializationException: Type 'objectdb.java.util.Date' was not included in the set of types which can be serialized by this SerializationPolicy or its Class object could not be loaded. For security purposes, this type will not be serialized.: instance = Sat Jan 29 00:00:00 PST 2011    at com.google.gwt.user.server.rpc.impl.ServerSerializationStreamWriter.serialize(ServerSerializationStreamWriter.java:614)  ... I have implemented serializarion for all of mine Data Transfer Object. But still I am getting this error. Note: (In gwt ... block. Avoid overflow of published source code examples by breaking long lines . You may mark in ...