Chapter 3 Building XML Models

Deriving by union

You can derive an element or simple type by union to define it as a collection of built-in and simple data types.

Steps To define an element or simple type derivation by union:

  1. Open the property sheet of an element or simple type, and select Union in the Derivation list.

    For elements, the Embedded type field is set to Simple.
  2. Click the Properties tool to the right of the Derivation box to open the union property sheet:
  3. Enter an ID and member types for the union.
  4. [optional] Click the Union Types tab and add appropriate simple types to the union.
  5. Click OK to close the union property sheet and return to the element or simple type.

Union property sheet General tab

The General tab of a simple type union property sheet displays the following properties:

Property Description
ID ID of the simple type union. Its value must be of type ID and unique within the model containing the simple type union
Member Types White space separated list of built-in data types. Values must be qualified names (See Glossary)

Union property sheet Union Types tab

The Union Types tab of a simple type union property sheet displays a list where you can add simple types using the Add Simple Type tool.

 

Copyright (C) 2007. Sybase Inc. All rights reserved.