New Object-Relational Features

This section describes the new object-relational features of Oracle9i Release 1 (9.0.1).

Oracle9i New Object-Relational Features

• SQL type inheritance

  Specialized versions of user-defined types can be defined as subtypes in a SQL type hierarchy.

  See Also: Chapter 2, section "Type Inheritance"

• Object view hierarchies

  Hierarchies can be created of object views based on some or all of the types in a type hierarchy. Object view hierarchies simplify targeting a particular subtype (and perhaps its subtypes) in queries and other operations.

  See Also: Chapter 5, section "Object View Hierarchies"

• Type evolution

  User-defined SQL types can be changed, or evolved, instead of having to be recreated.

  See Also: Chapter 6, section "Type Evolution"

• User-defined aggregate functions

  Custom aggregate functions can be defined for working with complex data.

  See Also: Chapter 6, section "User-Defined Aggregate Functions"

• Generic and transient datatypes

  External procedures can be given fields or parameters of a generic type that can contain values of any scalar or user-defined type, making it unnecessary to implement multiple versions of the same external procedure just to handle multiple datatypes.

  See Also: Chapter 6, section "Transient and Generic Types"

• Function-based indexes

  Function-based indexes can be built on type method functions.

  See Also: Chapter 8, section "Function-Based Indexes on the Return Values of Type Methods"

• Multi-level collections

  Collections (varrays and nested tables) can contain elements that are themselves collections or have attributes that are.

  See Also: Chapter 2 and Chapter 5

• C++ interface to Oracle

  A C++ interface (OCCI) to Oracle, built on top of OCI, enables you to use the object-oriented features, native classes, and methods of the C++ programing language to access the Oracle database.

  See Also: Chapter 3, section "Oracle C++ Call Interface (OCCI)"

• Java object storage

  You can now create SQL types mapped to existing Java classes to provide persistent storage for Java objects. Such SQL types are called SQL types of Language Java, or SQLJ types.

  See Also: Chapter 3, section "Java: JDBC, Oracle SQLJ, JPublisher, and SQLJ Object Types"