About composite

manual

JPA Primary Key

Explains how to define and use primary keys in JPA, including composite and embedded primary keys.... supports explicit standard JPA primary keys, including composite primary keys and automatic sequential value generation . This is ... Application Set Primary Key Composite Primary Key Embedded Primary Key ...

 
manual

Index Definition

Describes how to define indexes in JPA entity classes and explains how indexes are used in JPQL queries.... topics: Single Field Index Composite Index Multi Part Path Index Indexes in Queries ... fields (not on primary key / version fields). Composite Index A composite index is an index on more than one persistent ...

 
forum_thread

possible index required for improving query performance

Hi,   I have the following entity class:   @Entity @Table @Indices({ @Index(members={"relationshipType", "party"}), @Index(members={"relationshipType", "otherParty"}),     @Index(members={"relationshipType"}) }) @XmlRootElement public class Relationship implements Comparable<Relationship> { ... in the existing index). Notice that a composite index can be used as a single index of the first element (with a ... the second or third element, so the order of elements in a composite index makes a difference. ObjectDB Support ...

 
forum_thread

Composite indexes

Hi, I read your manual about defining Indexes for JPA Entities (http://www.objectdb.com/java/jpa/entity/index), but I still have some problems understanding how and when should I use them.   Let's start with some example then. Assume we have an entity that represents an interior design image, called Inspiration : ...   Here are my questions regarding composite indexes : #1. First of all - the first member in composite index should be a field that is most commonly used in WHERE clauses ...

 
forum_thread

composite index not used in query

we defined a composite index for class Action: @Index(name="ssst",members={"startDate","state","subType","type"}) and an index for the OneToMany @OneToMany(fetch=FetchType.LAZY) @Index  public List<ObjectNode> objectsInCharge = new ArrayList<ObjectNode>(); on running a query like ... 13:13 we defined a composite index for class Action: @ Index ( name = ... startDate > ? 1 ) ) the composite index is not used, query plan:  Step 1: Process Action ...

 
forum_thread

Multi part paths in a composite index must have the same length

Hi, I am trying to create some index in a DB - but I get an exception when i try to commit. Exception in thread "main" [ObjectDB 2.6.0_01] javax.persistence.PersistenceException Invalid index path 'tStamp.value / instrumentId' in type Entities.OrderBookNew (error 328) at com.objectdb.jpa.EMImpl.createQuery(EMImpl.java:958)   Here is how the class of the persisted object looks like ... is just a simple wrapper. Multi part paths in a composite index must have the same length . Therefore , the following ... technical issue with enabling such an index. A composite index with components of different lengths is forbidden because it ...

 
forum_thread

Problem with Composite indices

Hi, I want to realize the following: I have 2 classes, one Client class which looks like: public class Client { @Index (unique = "true") private String name; } and a User class which looks like: ... to be enforced by the application. Unfortunately a composite index on a field + a collection is not allowed. ...

 
forum_thread

Merge failure with composite primary key

It was working well with previous releases and now is failing: Exception in thread "main" [ObjectDB 2.3.7_20] javax.persistence.EntityNotFoundException Entity is not found: MergeTest#('Hello',0) (error 631) at com.objectdb.jpa.EMImpl.merge(EMImpl.java:451) at MergeTest.main(MergeTest.java:19)   Thanks. ... object), and build 2.3.7_21 should fix it. The composite primary key issue is unclear, since switching to a single primary key ...

 
issue

JPA Composite Key make Object Db throws "Unexpected exception (Error 990)"

Hello Object Db community :) I am using this wonderful library and I caught a strange exception while testing the "composite key" feature in JPA. Let's see what I am doing : @Entity public class Book {     @EmbeddedId BookId id; } @Embeddable Class BookId {     Integer bookIdCountry;     ECountry country; } My BookId contains 2 attributes: One Integer and one enum. ... and I caught a strange exception while testing the "composite key" feature in JPA. Let's see what I am doing : ...

 
page

ObjectDB Object Database Features

ObjectDB provides a rich set of features, many of them as the result of supporting the JPA and JDO APIs.... Single field and multi field ( composite ) indexes. Collection and ... @Id field. Composite primary key - multiple @Id fields or a @EmbeddedId field. ...