Elements (XSM)

Elements are the basic building blocks of an XML model.

An XML model is a tree structure of elements where child elements are attached to parent elements. For example:

Generated schema:

In a schema, elements are declared with <element> tags.

There are two broad kinds of elements:

Global elements - have no parent element in a diagram, and are directly linked to the <schema> tag (root element) in a schema. They can be reused in the model through referencing elements (see "XML_declaration" in the example)
Local elements - have a parent element in a diagram, and are unique within their parent scope. They can be defined by reference to a global element (see the Reference property in Element Properties).

Note: In a model targeted with the XML-Data Reduced language, local elements are first declared separately, like global elements (with the <ElementType> tag and a name attribute), then within their parent element (with the <element> tag and a type attribute).

Extract of an XDR file:

Parent elements are linked to their child elements through group particles (sequence, choice or all), which contain a group of child elements (see the Group type property in Element Properties).

You can derive an XSD element data type to extend or restrict its values (see the Derivation property in Element Properties).

Creating an Element
You can create an element from the Toolbox, Browser, or Model menu.
Element Properties
To view or edit an element's properties, double-click its diagram symbol or Browser or list entry. The property sheet tabs and fields listed here are those available by default, before any customization of the interface by you or an administrator.
Linking Child Objects to Elements
XML objects do not support standard PowerDesigner link objects. To link a child object to an element, you must click the child object tool in the Toolbox and then click the element symbol in the diagram. This will automatically create a link between both objects.
Manipulating XML Objects Graphically
The graphical interface of PowerDesigner allows you to manipulate your XML schema by moving XML objects within the Browser, within the diagram, or by dragging them from the Browser into the diagram or from the diagram into the Browser.

Parent topic: XML Diagrams