NPersistence Reference Guide
Defines a single-valued association to another entity class that has many-to-one multiplicity. It is not normally necessary to specify the target entity explicitly since it can usually be inferred from the type of the object being referenced.

If the relationship is bidirectional, the non-owning OneToMany entity side must used the mappedBy element to specify the relationship field or property of the entity that is the owner of the relationship.

The ManyToOne annotation may be used within an embeddable class to specify a relationship from the embeddable class to an entity class. If the relationship is bidirectional, the non-owning OneToMany entity side must use the mappedBy element of the OneToMany annotation to specify the relationship field or property of the embeddable field or property on the owning side of the relationship. The dot (".") notation syntax must be used in the mappedBy element to indicate the relationship attribute within the embedded attribute. The value of each identifier used with the dot notation is the name of the respective embedded field or property.

Examples

CopyC#
Example 1:

[ManyToOne(optional=false)]
[JoinColumn(name="CUST_ID", nullable=false, updatable=false)]
public Customer getCustomer() { return customer; }


Example 2:

[Entity]
   public class Employee {
   [Id] int id;
   [Embedded] JobInfo jobInfo;
   ...
}

[Embeddable]
   public class JobInfo {
   String jobDescription; 
   [ManyToOne] ProgramManager pm; // Bidirectional
}

[Entity]
   public class ProgramManager {
   [Id] int id;
   [OneToMany(mappedBy="jobInfo.pm")]
   Collection<Employee> manages;
}

Namespace: NPersistence
Assembly: NPersistence (in NPersistence.dll) Version: 2.0.0.0 (2.0.0.0)

Syntax

   
 C# 
public sealed class ManyToOne : Attribute

Members

         
 All Members  Constructors   Fields  
 Public

 Protected
 Instance

 Static 
 Declared

 Inherited
 XNA Framework Only 

 .NET Compact Framework Only 

 MemberDescription
ManyToOne()()()()
Initializes a new instance of the ManyToOne class
Cascade
(Optional) The operations that must be cascaded to the target of the association. By default no operations are cascaded.
Fetch
(Optional) Whether the association should be lazily loaded or must be eagerly fetched. The EAGER strategy is a requirement on the persistence provider runtime that the associated entity must be eagerly fetched. The LAZY strategy is a hint to the persistence provider runtime.
Optional
(Optional) Whether the association is optional. If set to false then a non-null relationship must always exist.
TargetEntity
(Optional) The entity class that is the target of the association. Defaults to the type of the field or property that stores the association.

Inheritance Hierarchy

System..::..Object
  System..::..Attribute
    NPersistence..::..ManyToOne

See Also