XML Diagram Objects

PowerDesigner supports all the objects necessary to build XML diagrams.

An XML model represents the structure of a potential or existing XSD, DTD, or XDR through a tree structure of child elements attached to parent elements.

Elements are the basic describing items of an XML model. They can be made of other elements combined in different ways through group particles. Elements are specified by attributes and data types, which can be predefined or user-defined. Simple and complex data types can be defined as global (directly linked to the <schema> tag) or local (embedded in an element declaration).

Object

Tool

Symbol

Description

Element



The basic object of an XML model. An element can contain other elements or attributes. See Elements (XSM).

Any



Any type of object. Can only be attached to a sequence or a choice group particle. See Any Elements (XSM).

Attribute

N/A

N/A

Additional information about an element or a complex type. Defined by a built-in data type or a simple data type. See Attributes (XSM).

Group



A group of elements arranged by a group particle. Defined once and reused through references. See Groups (XSM).

Attribute Group

N/A

N/A

A group of attributes, defined once and reused in the model through references. See Attribute Groups (XSM).

Simple Type

N/A

N/A

[XSD only] Used in the case of elements or attributes with text-only content. See Simple Types (XSM).

Complex Type



[XSD only] Used to introduce elements or attributes within an element declaration. See Complex Types (XSM).

Sequence



This group particle arranges a set of elements, where all the elements must appear at least once in the order of their declaration. See Group Particles (XSM).

Choice



This group particle arranges a set of elements, from which one element must be chosen. See Group Particles (XSM).

All



This group particle arranges a set of elements, where each element can appear or not, in any order. See Group Particles (XSM).

Instruction

N/A

N/A

An import, include, or redefine instruction. See Instructions: Import, Include and Redefine (XSM)

Derivation

N/A

N/A

Extends or restricts the values of elements and simple and complex types. See Derivations: Extensions, Restrictions, Lists and Unions (XSM)

Constraint

N/A

N/A

[XSD only] Specifies uniqueness of element values. See Constraints: Keys, Uniques, and KeyRefs (XSM)

Annotation

N/A

N/A

Provides documentation or application information. See Annotations (XSM)

Entity

N/A

N/A

[DTD only] Specifies a predefined value or external XML or non-XML file. See Entities (XSM).

Notation

N/A

N/A

Defines and processes non-XML objects within an XML model. See Notations (XSM)