About primary key

manual

Database Explorer

Explains how to run and use the ObjectDB object database Explorer to view and manage Java/JPA/JDO objects visually.... any). An entity object can be specified by type and primary key separated by # (e.g. Point#1). A collection can be specified as a comma ...

 
api-jpa

JoinColumn.unique

(Optional) Whether the property is a unique key.(Annotation Element of javax.persistence.JoinColumn)

 
api-jpa

MapKeyColumn.table

(Optional) The name of the table that contains the column.(Annotation Element of javax.persistence.MapKeyColumn)

 
api-jpa

JoinColumn.referencedColumnName

(Optional) The name of the column referenced by this foreign key column.(Annotation Element of javax.persistence.JoinColumn)

 
manual

Database Explorer

Explains how to run and use the ObjectDB object database Explorer to view and manage Java/JPA/JDO objects visually.... any). An entity object can be specified by type and primary key separated by # (e.g. Point#1). A collection can be specified as a comma ...

 
manual

Setting and Tuning of JPA Queries

Explains various JPA query settings - result range, flush and lock.... primaryKey) EntityManager's method Find by primary key. See JavaDoc Reference Page... . However, query execution is ...

 
forum_thread

Broken @ManyToOne reference

Hi, I have objects of type A belonging to objects of type B, defined as follows: @MappedSuperclass public abstract class A {   @Id   @ManyToOne(fetch = FetchType.EAGER, cascade=CascadeType.ALL, optional=false)   private B b;   @Id   @Column(length = 36)   private String stringId; } @MappedSuperclass public abstract class B {   @Id   private String name; } ... because  Main.CHILD_ID is only part of the primary key now. ObjectDB Support ObjectDB - Fast Object ...

 
forum_thread

Insertion Speed Rate and Batch Load

1. I got about 10K inserts / second, is it normal? I would expect more than that, like close to 100K/second. I can definitely do 80K inserts/seconds on Oracle with batch insert on table with one primary key. 2. Is batch update/insert operation supported? I attached the files. ... on Oracle with batch insert on table with one primary key. 2. Is batch update/insert operation supported? I attached ...

 
forum_thread

calling persist on an object more than once

results in an error (613) when the transaction is commited: [ObjectDB 2.2.4] javax.persistence.RollbackException Failed to commit transaction: Attempt to reuse an existing primary key value (common.model.UserSession:13) (error 613) at com.objectdb.jpa.EMImpl.commit(EMImpl.java:271) at javax.jdo.Transaction$commit.call(Unknown Source)   I submit that there are a number of problems with this: a) the error message is not helpful ... Failed to commit transaction: Attempt to reuse an existing primary key value (common.model.UserSession:13) (error 613) at ... entity again and persisting a new entity with existing ID (primary key), so the error message is more general. There might be a place for ...

 
manual

ORDER BY clause (JPQL / Criteria API)

Explains how to use the ORDER BY clause in a JPA/JPQL query.... expressions. In this case, the first expression is the primary order expression. Any additional order expression is used to order ... objects ordered by currency as the primary sort key and by name as the secondary sort key: SELECT c . currency ...