26 Configuring an Object-Relational Data Type Descriptor

This chapter describes the various components that you must configure to be able to use an object-relational data type descriptor.

This chapter includes the following sections:

For information on how to configure TopLink descriptor options common to two or more descriptor types, see Chapter 119, "Configuring a Descriptor".

Table 26-1 lists the configurable options for a relational descriptor.

26.1 Introduction to Object-Relational Data Type Descriptor Configuration

Table 26-1 lists the configurable options for an object-relational data type descriptor.

Table 26-1 Configurable Options for Object-Relational Data Type Descriptor

Option to Configure JDeveloper TopLink Workbench Java

Field ordering (see Section 26.2, "Configuring Field Ordering")

 Unsupported Unsupported Supported

Primary keys (see Section 119.2, "Configuring Primary Keys")

 Unsupported Unsupported Supported

Read-only descriptors (see Section 119.3, "Configuring Read-Only Descriptors")

 Unsupported Unsupported Supported

Unit of work conforming (see Section 119.4, "Configuring Unit of Work Conforming at the Descriptor Level")

 Unsupported Unsupported Supported

Query keys (see Section 119.10, "Configuring Query Keys")

 Unsupported Unsupported Supported

Cache expiration (see Section 119.16, "Configuring Cache Expiration at the Descriptor Level")

 Unsupported Unsupported Supported

Amendment methods (see Section 119.35, "Configuring Amendment Methods")

 Unsupported Unsupported Supported

Reading subclasses on queries (see Section 119.19, "Configuring Reading Subclasses on Queries")

 Unsupported Unsupported Supported

Inheritance for a child class descriptor (see Section 119.20, "Configuring Inheritance for a Child (Branch or Leaf) Class Descriptor")

 Unsupported Unsupported

Supported.

Inheritance for a parent class descriptor (see Section 119.21, "Configuring Inheritance for a Parent (Root) Descriptor")

 Unsupported Unsupported Supported

Inheritance expressions for a parent class descriptor (see Section 119.22, "Configuring Inheritance Expressions for a Parent (Root) Class Descriptor"

 Unsupported Unsupported Supported

Inherited attribute mapping in a subclass (see Section 119.23, "Configuring Inherited Attribute Mapping in a Subclass")

 Unsupported Unsupported

Supported.

Cache type and size (see Section 119.12, "Configuring Cache Type and Size at the Descriptor Level")

 Unsupported Unsupported Supported

Domain object method as an event handler (see Section 119.24, "Configuring a Domain Object Method as an Event Handler")

 Unsupported Unsupported Supported

Descriptor event listener as an event handler (see Section 119.25, "Configuring a Descriptor Event Listener as an Event Handler")

 Unsupported Unsupported Supported

Locking policy (see Section 119.26, "Configuring Locking Policy")

 Unsupported Unsupported Supported

Copy policy (see Section 119.29, "Configuring Copy Policy")

 Unsupported Unsupported Supported

Instantiation policy (see Section 119.28, "Configuring Instantiation Policy")

 Unsupported Unsupported Supported

Wrapper policy (see Section 119.32, "Configuring Wrapper Policy")

 Unsupported Unsupported Supported

History policy (see Section 119.31, "Configuring a History Policy")

 Unsupported Unsupported Supported

Returning policy (see Section 119.27, "Configuring Returning Policy")

 Unsupported Unsupported Supported

For more information, see Chapter 21, "Introduction to Relational Descriptors".

26.2 Configuring Field Ordering

If your object-relational data type data source driver uses JDBC indexed arrays, you can specify the order in which TopLink persists object attributes to define the field index.

26.2.1 How to Configure Field Ordering Using Java

Use ObjectRelationalDescriptor method addFieldOrdering to specify the field ordering. Example 26-1 shows how to specify the order of the object-relational data type database fields OBJECT_ID, F_NAME, and L_NAME for the Employee descriptor.

Example 26-1 Field Ordering

descriptor.addFieldOrdering("ID");
descriptor.addFieldOrdering("F_NAME");
descriptor.addFieldOrdering("L_NAME");