Defining derivations

Defining derivations

You use derivations when you want to extend or restrict the values of simple and complex types.

An XML model allows you to derive:

Simple types by restriction, list or union

Complex types by extension or restriction

Derivation in element property sheet

When you define a derivation in an element property sheet, a simple or a complex type is automatically created within the element declaration (See Preview page). The Embedded type property is automatically set to Simple or Complex, and the Content property to Simple or Complex in the case of an embedded complex type.

Deriving by extension

You derive a complex type by extension when you want to extend the values of its base type.

For example:

USaddress is a derivation by extension of the address complex type.

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PowerDesigner

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Sybase XML manual Defining derivations, Deriving by extension, Derivation in element property sheet, 102