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Embedded in JDO metadata not working in objectDB 2.x ?

Hi, I am using JDO access to the database with the persistence defined in package.jdo XML metadata files. In those metadata files I have few persistence-capable classes which had extents in ObjectDB 1 (with an OID for every instance) and all other classes were embedded (so without extent and own OID) in those few peristence-capable ones. Example of JDO metadata: ... and own OID) in those few peristence-capable ones. Example of JDO metadata: <class name = "ProjectPart" > ... </class > So as You see in the example I have the instances of RackGroupList embedded inside the instance of ...

 
issue

Schema-Update: Rename superclass and remove one subclass

Hello, we renamed a superclass and removed one of the subclass. If we then try to open the Database (with ObjectDB-Explorer) we get a "Failed to generate dynamic type ..."   Small Example: Generate Database ... to generate dynamic type ..."   Small Example: Generate Database public static void main ... we access the prevous create Database with the following example: public static void main ( String [ ...

 
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How to use JOIN FETCH?

The ObjectDB manual (http://www.objectdb.com/java/jpa/query/jpql/from) gives an example of using JOIN FETCH to avoid excessive round trips to the database: ... ) gives an example of using JOIN FETCH to avoid excessive round trips to the database: ... I've tried a few variants of the following example, and haven't been able to get this to work.  See the code ...

 
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Dirty checking

Hi, wondering if anyone knows the best way to detect which objects have been changed in the database. ie: which objects, and which collections of objects, have been dirtied.     ... were Added, Deleted, and Changed. That is a simple example, more complex views are composed of data from several different Entity ... etc. So, now let's give a simple concrete example, with just 2 classes (the actual application has 20 Entity classes and ...

 
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Modifier operations

Hi, Today I was reading about different NoSQL databases. One of those database - MongoDB - has a very nice feature, especially for web applications - modifier operations. The whole trick for those operations is to change some value in object without pulling this object from database. So for example we have class: public class WebVisit { public String url; // key public int visitsCount; } As for now I have to pull this class from database: ... object without pulling this object from database. So for example we have class: public class WebVisit { ... I totally forget about update statement for such simple example :) edit ...

 
issue

ObjectDB 2 JDO Manual

The new ObjectDB Manual describes how to use ObjectDB 2 with JPA. An additional manual that focuses on using ObjectDB 2 with JDO can help JDO users. But since writing a new manual and then maintaining two similar manuals, one for JPA and the other for JDO requires sufficient effort, this will be done only if there is sufficient demand.  ... too. I use ObjectDB as an esy-to-install and free example of an object database in a university course on database technology. ... support of JDO 2 is when you don't even have a small demo example. I understand that keeping two manuals up to date is a lot of ...

 
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Tomcat + JPA Problem

Hi i tried to setup the example from your webpage (jpa - Tomcat with Ecplipse) and i always get this Error: [ObjectDB 2.1.0] class "javax.persistence.Entity"'s signer information does not match signer information of other classes in the same package   ... Hi i tried to setup the example from your webpage (jpa - Tomcat with Ecplipse) and i always get this ... of Java, Eclipse and Tomcat that you are using. This example was tested with Tomcat 6. Are you using Tomcat 7? ...

 
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java.sql.Time field off by 30 minutes

Hihi, I'm wondering if this is a bug. I have a simple entity with java.sql.Time field. On writing and readback, the field is found to be 30 minutes off. It is observed on objectdb explorer as well. Timestamp works perfectly fine. Ps. dont think its a UTC issue. My system is set at far off UTC+30min time.   ... ObjectDB). Can you provide a simple runnable example to demonstrate this? ObjectDB Support ...

 
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Is it ok to put list or map of embeddable objects in entity ?

Hi, Is it ok to put list or map of embeddable objects in entity? I mean, for example : @Entity public class Entity_A {     (...)     @Embedded     List<Class_B> bList;     @Embedded     Map<String, Class_C> cMap; (...) } where Class_B and Class_C are annotated as @Embeddable ? In the examples, there is only situation where there is one single instance of embeddable class in entity. And what happens if I do operation like : ... list or map of embeddable objects in entity? I mean, for example : @ Entity public class Entity_A { ...

 
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Spring 4 setup

Can someone provide an example of setup ObjectDB embeded to be used with Spring4? Existing examples is like for Spring3 and I can't figure how to use ObjecDB in Spring tutorial: http://spring.io/guides/gs/accessing-data-jpa/   Thanx. ... Can someone provide an example of setup ObjectDB embeded to be used with Spring4? Existing ...