About field


JPA Annotations for Relationships

Reference (JavaDoc) of JPA 2 relationship annotations, including @ManyToMany, @ManyToOne, @OneToMany, @OneToOne, @OrderBy and @MapKey. Relationships are persistent fields in persistable classes that reference other entity objects. The four relationship modes are represented by the following annotations: javax.persistence.ManyToMany javax.persistence.ManyToOne ...


Step 6: Design a BIRT Report Table

Explains how to design a BIRT report table using ObjectDB and JPA.... , select the data set (e.g. Points by X ) in the third field and click OK . Fill the table with data ...


String Contains Query Result - Possible?

Hi, I have a managed database for an Entity, "Program", filled with String fields, "description", that are effectively unique sub-strings of a system generated description. Example: System: For Series Sales usage: 6014-Private Individual Swim Lessons  10-Pack Database: 6014-Private Individual Swim Lessons  10-Pack I would like to know if it is possible to have a query return the "Program" object using the System Description? I've considered doing something similar to... ... database for an Entity, "Program", containing a String field, "description", that is effectively a unique sub-string of a system ...


Step 2: Entity Class and Persistence Unit

Explains how to define a JPA entity class and a persistence unit (persistence.xml) in an Eclipse Spring MVC web application project. To store objects in an ObjectDB database using JPA we need to define an entity class: Right click the project node (in the [Package Explorer] window), select  New > Source Folder , enter src/main/java as Folder ...


Stacktrace in Explorer when running query

Hello, whenever I run a query in Explorer I get the following stacktrace (cf. attached file). My environment is: macOS Sierra 10.12.1 with java version "1.8.0_112" Is there anything I can do to fix this? Many thanks in advance Alex #1 2016-12-05 13:54 Hello, whenever I run a query in Explorer I get the following stacktrace (cf. attached file). My ...



This class is for identity with a single int field.(Class of JDO)



Used in the mapping of associations.(Annotation of JPA)



The number of instances of multi-valued fields retrieved by queries.(Annotation Element of javax.jdo.annotations.FetchPlan)



Null indicator column for this member.(Annotation Element of javax.jdo.annotations.Persistent)


Exception in thread "main" java.lang.NoSuchFieldError: __odbTracker

Hi   there is something wrong with enhancement process I got that class was succesfully processed, log has size 0, enhancer is from build objectdb-2.2.8_08 and during object creation when some filed is initialised i got an exception   Exception in thread "main" java.lang.NoSuchFieldError: __odbTracker at com.package.Network.__odbSet_Connections(Network.java:1) at com.package.Network.<init>(Network.java:95) at com.package.EnhancementTest.main(EnhancementTest.java:14)   ... but it has no __odbTracker field which is referenced in generated method:  __odbSet_Connections ...