Attributes are used to give additional information about elements.
There are global and local attributes:
Global attributes are defined with the Model menu. In a schema, they are directly linked to the <schema> tag (root element). They can be reused for any element in the model through references (See "NUMBER" attribute in the generated schema)
Local attributes only apply to the elements in which they are created. They can be defined by reference to a global attribute (See Reference property)
Extract of an XDR file:
You can derive an attribute data type to extend or restrict its values. (Only with a model targeted with XSD)
For example:
Generated schema:
In a schema, attributes are declared with <attribute> tags.