DiscriminatorColumn Class
NPersistence Reference Guide
Specifies the discriminator column for the

SINGLE_TABLE and

JOINED Inheritance mapping strategies.

The strategy and the discriminator column are only specified in the root of an entity class hierarchy or subhierarchy in which a different inheritance strategy is applied

If the DiscriminatorColumn annotation is missing, and a discriminator column is required, the name of the discriminator column defaults to "DTYPE" and the discriminator type to STRING()()()().

Examples

CopyC#
Example:

[Entity]
[Table(name="CUST")]
[Inheritance(strategy=SINGLE_TABLE)]
[DiscriminatorColumn(name="DISC", discriminatorType=STRING, length=20)]
public class Customer { ... }

[Entity]
public class ValuedCustomer extends Customer { ... }

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

Syntax

   
 C# 
public sealed class DiscriminatorColumn : Attribute

Members

         
 All Members  Constructors   Fields  
 Public

 Protected
 Instance

 Static 
 Declared

 Inherited
 XNA Framework Only 

 .NET Compact Framework Only 

 MemberDescription
DiscriminatorColumn()()()()
Initializes a new instance of the DiscriminatorColumn class
ColumnDefinition
(Optional) The SQL fragment that is used when generating the DDL for the discriminator column. Defaults to the provider-generated SQL to create a column of the specified discriminator type.
DiscriminatorType
(Optional) The type of object/column to use as a class discriminator. Defaults to STRING()()()().
Length
(Optional) The column length for String-based discriminator types. Ignored for other discriminator types.
Name
(Optional) The name of column to be used for the discriminator.

Inheritance Hierarchy

System..::..Object
  System..::..Attribute
    NPersistence..::..DiscriminatorColumn

See Also