many-to-one

Two class: Department Task One department can have many tasks. One task can only belong to one department. So use one-to-many or many-to-one? one-to-many class Department{ private Set tasks; } class Task{ ...... } // Department.hbm.xml .... <set name="tasks"> <key column="departId" /> <one-to-many class="Task" /> </set> ..... many-to-one class Department{ } class Task{ Department depart; } // Task.hbm.xml .... <property name="depart"> <many-to-one class="Department" /> </property> ..... What's the difference? BTW,what is the difference between use the set and list? And example using list(xml

I hope someone can help me find an answer. I'm working with a legacy database and I can't change any of the preexisting tables, because other apps depend on them. I have three main existing tables: A,B,C . A has a column with reference to B(many to one relation). The problem is that it should have a relation to C not to B. So I have created a *-1 mapping BC. Tables: A,B,C,BC (all have ID field) A-B many to one B-C many to one through BC Needed:A-C without altering A,B or C I don't want to have java entities for B or BC, just A and C, and A should have a field A.c So far I have tried using the

Could some please explain me why Having a @Filter on a @ManyToOne relation does not work? Here i have a really simple example showing this: I have created two simple table in my database (foo and bar) Foo: id/id_bar bar: id/name/state (state can be active or inactive) and my Entities: @Entity @FilterDef(name = "foo_active") @Table(name = "foo") public class Foo extends AbstractTimestampEntity implements Serializable { private static final long serialVersionUID = 1L; @Id @Column(name = "id") private Integer id; @ManyToOne(cascade = CascadeType.DETACH, fetch = FetchType.LAZY) @JoinColumn(name =

I'll simplifly my code, I have te next: Doctor entity: use ...\...\Entity\Paciente; class Doctor extends Usuario { public function __construct() { ... $this->pacientes = new ArrayCollection(); ... } /** * Número de colegiado - numColegiado * * @var string * * @ORM\Column(name="numColegiado", type="string", length=255, unique=true) */ protected $numColegiado; /** * @ORM\OneToMany(targetEntity="Paciente", mappedBy="doctor") * @var \Doctrine\Common\Collections\ArrayCollection */ private $pacientes; ... } Paciente entity: use \...\...\Entity\Doctor; ... class Paciente extends Usuario { } /** *

Let's first describe my situation. I am using Symfony2 and I have a problem with a relationship between my entities. I have two entities that are linked together. The two entities are AssociationQuestion and AssociationPossibleAnswer . I am currently creating a questionary software where one would have to link one possible answer on the left to another one possible answer on the right, such as in the following example: Currently, I'm planning on having two attributes that are arrays in class AssociationQuestion that would hold many AssociationPossibleAnswer objects. The first array would

I am working on a JPA project. I need to use a @OneToMany mapping on a class that has three primary keys. You can find the errors and the classes after this. javax.persistence.PersistenceException: No Persistence provider for EntityManager named JTA_pacePersistence: Provider named oracle.toplink.essentials.PersistenceProvider threw unexpected exception at create EntityManagerFactory: javax.persistence.PersistenceException javax.persistence.PersistenceException: Exception [TOPLINK-28018] (Oracle TopLink Essentials - 2.0.1 (Build b09d-fcs (12/06/2007))): oracle.toplink.essentials.exceptions

If have an entity A with a bidirectional one-or-zero-to-one mapping with entity B. The mapping is as follows: <class name="EntityA" table="TABLE_A" mutable="true" lazy="true"> <id name="idA" type="long" column="pk_a" unsaved-value="null"> <generator class="sequence"> <param name="sequence">pk_a_seq</param> </generator> </id> <one-to-one name="propertyB" class="EntityB" property-ref="propertyA" constrained="true" outer-join="false"/> </class> and <class name="EntityB" table="TABLE_B" mutable="true" lazy="true"> <id name="idB" type="long" column="pk_b" unsaved-value="null"> <generator class=