Defining types in a database package

Chapter 15 DBMS-Specific Features

Defining types in a database package

A type is a user-defined composite datatype that encapsulates a data structure along with the functions and procedures needed to manipulate the data. You can also define subtypes of object types: a subtype contains all the attributes and methods of the parent type, it can contain additional attributes and can override methods from the type.

Types have the following properties:

Property	Description
Name	The name of the item which should be clear and meaningful, and should convey the item's purpose to non-technical users.
Code	The technical name of the item used for generating code or scripts, which may be abbreviated, and should not generally include spaces.
Comment	Additional information about the type.
DB Package	Name of the database package to which the type belongs.
Type	Allows you to declare the type as type or subtype.
Public	Allows you to declare the type in the package specification and to permit use from outside the database package. A private type (check box deselected) is only defined in the package body.

Definition

This tab is used to declare the type contents.

The following example defines the type bank_account:

CREATE TYPE Bank_Account AS OBJECT (
acct_number INTEGER(5),
balance REAL,
status VARCHAR2(10),
);