
Chapter 2 Building an XML model
Defining simple types
You can only define simple types in a model targeted with XSD.
What is a simple type?
A simple type is a data type definition for elements or attributes with text- only content.
A simple type cannot contain elements or attributes.
A simple type is defined by derivation of an existing simple type 
There are three kinds of derivation for a simple type:
Type of derivation | Description | 
List  | The simple type contains a white   | 
  | values of an inherited simple type  | 
Restriction  | The simple type has a range of values restricted to a  | 
  | subset of those of an inherited simple type  | 
Union  | The simple type contains a union of values of two or  | 
  | more inherited simple types  | 
  | 
  | 
For more information on simple type derivations, see section Defining derivations.
Once defined in a model, a simple type can be reused in the definition of an attribute, an element or a complex type.
Example of a simple type in a schema:
XSM User's Guide  | 89  |