Advanced XML Schema Patterns for Databinding Version 1.0

1. Introduction

A databinding tool generates a mapping between XML documents which conform to an [XML Schema 1.0] schema and an internal data representation. For example, a Web services databinding tool may use [XML Schema 1.0] descriptions inside a [WSDL 2.0] document to produce and consume [SOAP 1.2] messages in terms of data structures in a programming language or data held inside a database.

State of the art databinding implementations have displayed uneven and inconsistent support of the W3C [XML Schema 1.0] Recommendation. XML Schema provides a wide variety of methods for describing the same XML structure, conversely a concept such as "null" may be represented in a wide variety of different ways.

The result of these issues is impaired interoperability and a poor user experience of databinding tools:

rejecting valid XML Schema documents,
rejecting valid XML instance documents, and
making the content of valid XML instance documents unavailable in mapped data structures.

This specification provides a advanced set of example [XML Schema 1.0] constructs and types in the form of concrete [XPath 2.0] expressions. These patterns are known to be in widespresd use and considered to be compatible with databinding implementations.

Implementers of databinding tools may find these patterns useful to represent simple and common place data structures. Ensuring tools recognise at least these simple [XML Schema 1.0] patterns and present them in terms most appropriate to the specific language, database or environment will provide an improved user experience when using databinding tools. It is inappropriate to use this specification to constrain the use of the [XML Schema 1.0] Recommendation.

1.1 Notational Conventions

All parts of this specification are normative, with the EXCEPTION of notes, examples, and sections explicitly marked as Non-Normative.

The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this specification are to be interpreted as described in [RFC 2119].

Each [XML Schema 1.0] pattern is defined using a single [XPath 2.0] expression constraining one or more [XML Schema 1.0] items.

Each [XML Schema 1.0] pattern is identified using a unique and stable URI [RFC 3986].

Assertions about documents and implementations that are not enforced by the normative patterns are marked by a dagger symbol (†) at the end of a sentence. Each assertion has been assigned a unique and stable identifier. The assertion identifiers MAY be used by implementations of this specification for any purpose, such as error reporting. The assertions and their identifiers are summarized in section C. Assertion Summary.

1.2 Namespaces

This specification uses a number of namespace prefixes throughout; they are listed in Table 1-1. Note that the choice of any namespace prefix is arbitrary and not semantically significant (see [XML Namespaces]).

Table 1-1. Prefixes and Namespaces used in this specification
Prefix	Namespace
xs	http://www.w3.org/2001/XMLSchema
xsi	http://www.w3.org/2001/XMLSchema-instance
soap11	http://schemas.xmlsoap.org/soap/envelope/
soap12	http://www.w3.org/2003/05/soap-envelope
wsdl11	http://schemas.xmlsoap.org/wsdl/
wsdl20	http://www.w3.org/2005/08/wsdl
pat	http://www.w3.org/2002/ws/databinding/patterns/6/09/
ex	http://www.w3.org/2002/ws/databinding/examples/6/09/

1.3 Document Conformance

A Document claiming conformance to this specification:

MUST use either the UTF-8 or UTF-16 [Unicode] encoding.^†
MAY include the [Unicode] Byte Order Mark (BOM).^†
MUST be a Well-formed [XML 1.0] document^†
MUST conform to the [XML Schema 1.0] Recommendation^†
MUST only contain [XML 1.0] element nodes and attribute nodes which form a part of one or more complete patterns contained in this and the [Basic Patterns] specifications.^†
MAY contain additional [XML 1.0] comment nodes and processing instruction nodes.^†

1.4 Implementation Conformance

An implementation that claims conformance to this specification:

SHOULD be able to process any valid [XML Schema 1.0] Document.^†
MUST be able to process any [XML Schema 1.0] Document conforming to this specification^†
MUST produce a data model exposing all of the [XML 1.0] element node and attribute node content described by the originating [XML Schema 1.0] Document.^†
MUST be able to consume any Well-formed [XML 1.0] Document which satisfies local-schema validity against the originating [XML Schema 1.0] Document exposing all of the [XML 1.0] element node and attribute node content in the data model.^†
MUST be able to produce Well-formed [XML 1.0] instance documents which satisfy local-schema validity against the originating [XML Schema 1.0] Document containing values exposed in the data model.^†
MAY consume Well-formed [XML 1.0] instance documents which do not satisfy local-schema validity against the originating [XML Schema 1.0] Document.^†
MAY allow the production of Well-formed [XML 1.0] instance documents containing values exposed in the data model which do not satisfy local-schema validity against the originating [XML Schema 1.0] Document.^†

Describing the form of the data model provided by a databinding implementation is beyond the scope of this specification. For example, the unconstrained built-in numeric primitive types, xs:decimal, xs:integer, xs:negativeInteger, xs:positiveInteger, xs:nonNegativeInteger and xs:nonPositiveInteger, do not map directly to native types in many programming languages and are likely to be presented as a toolkit specific construct or more generalised ways, such as a 'string'.

Note that although the patterns contained in this document are defined using [XPath 2.0], there is no requirement for a conformant implementation to support [XPath 2.0].

2. Schema Patterns

This section enumerates a series of concrete [XML Schema 1.0] patterns. Each pattern is identified by a URI [RFC 3986], defined using an [XPath 2.0] expression and accompanied by an example schema and one or more instance documents. This document offers no additional semantics for the schema patterns presented beyond those specified by the [XML Schema 1.0] Recommendation.

2.1 Properties

2.1.1 MixedContentElement

An [XML 1.0] document exhibits the MixedContentElement pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/MixedContentElement when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:element[@mixed = 'true']/ (@mixed)

2.1.2 MixedComplexContent

An [XML 1.0] document exhibits the MixedComplexContent pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/MixedComplexContent when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:complexContent[@mixed = 'true']/ (@mixed)

2.1.3 MixedContentType

An [XML 1.0] document exhibits the MixedContentType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/MixedContentType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:complexType[@mixed = 'true']/ (@mixed)

The following example [XML Schema 1.0] extract illustrates the use of the MixedContentType pattern within an [XML Schema 1.0] document [MixedContentType]:

<xs:element name="mixedContentType" type="ex:MixedContentType" />
<xs:complexType name="MixedContentType" mixed="true">
  <xs:sequence>
    <xs:element name="elem1" type="xs:string" />
    <xs:element name="elem2" type="xs:string" />
  </xs:sequence>
</xs:complexType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [MixedContentType01]:

  <ex:mixedContentType>
      <ex:elem1>Tagged Value</ex:elem1>

      mixed value
      
      
      <ex:elem2>Tagged Value</ex:elem2>
   </ex:mixedContentType>

as is the following element when included in an instance document [MixedContentType02]:

  <ex:mixedContentType>

      some text
      
      
      <ex:elem1>Tagged Value</ex:elem1>

      more text
      
      
      <ex:elem2>Tagged Value</ex:elem2>
   </ex:mixedContentType>

and the following element when included in an instance document [MixedContentType03]:

  <ex:mixedContentType>
      <ex:elem1>Tagged Value</ex:elem1>

      mixed text value
      
      
      <ex:elem2>Tagged Value</ex:elem2>

      mixed text value
   
   
   </ex:mixedContentType>

and the following element when included in an instance document [MixedContentType04]:

  <ex:mixedContentType>

      text mixed value
      
      
      <ex:elem1>Tagged Value</ex:elem1>
      <ex:elem2>Tagged Value</ex:elem2>

      some more text in a mixed value
   
   
   </ex:mixedContentType>

2.2 Import and Include

2.2.1 ImportSchemaNamespace

An [XML 1.0] document exhibits the ImportSchemaNamespace pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/ImportSchemaNamespace when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

./xs:import[not(@schemaLocation) and @namespace =
'http://www.w3.org/2001/XMLSchema']/ (., @namespace)

The following example [XML Schema 1.0] extract illustrates the use of the ImportSchemaNamespace pattern within an [XML Schema 1.0] document [ImportSchemaNamespace]:

<xs:importnamespace="http://www.w3.org/2001/XMLSchema" />
<xs:element name="importSchemaNamespace" type="xs:string" />

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [ImportSchemaNamespace01]:

  <ex:importSchemaNamespace>hello service</ex:importSchemaNamespace>

2.3 Global Element Declarations

2.3.1 GlobalElementUnqualifiedType

An [XML 1.0] document exhibits the GlobalElementUnqualifiedType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/GlobalElementUnqualifiedType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

./xs:element[@name and @type and not(contains(@type, ':'))]/
(., @name, @type)

2.3.2 ElementTypeDefaultNamespace

An [XML 1.0] document exhibits the ElementTypeDefaultNamespace pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/ElementTypeDefaultNamespace when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:element[@name and @type and not(contains(@type, ':'))]/
(@name, @type)

The following example [XML Schema 1.0] extract illustrates the use of the ElementTypeDefaultNamespace pattern within an [XML Schema 1.0] document [ElementTypeDefaultNamespace]:

<xs:element name="stringElementDefaultNamespace" type="string" />

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [ElementTypeDefaultNamespace01]:

  <ex:stringElementDefaultNamespace/>

as is the following element when included in an instance document [ElementTypeDefaultNamespace02]:

  <ex:stringElementDefaultNamespace>This is a string!</ex:stringElementDefaultNamespace>

2.3.3 GlobalElementAbstract

An [XML 1.0] document exhibits the GlobalElementAbstract pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/GlobalElementAbstract when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

./xs:element[@abstract='true']/ (@abstract)

2.3.4 GlobalElementAll

An [XML 1.0] document exhibits the GlobalElementAll pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/GlobalElementAll when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

./xs:element[@name]/xs:complexType/xs:all[xs:element]/
(../../(., @name), .., ., xs:element/(., @name))

2.3.5 GlobalElementChoice

An [XML 1.0] document exhibits the GlobalElementChoice pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/GlobalElementChoice when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

./xs:element[@name]/xs:complexType/xs:choice[xs:element]/
(../../(., @name), .., ., xs:element/(., @name))

2.3.6 GlobalElementComplexTypeSequenceExtension

An [XML 1.0] document exhibits the GlobalElementComplexTypeSequenceExtension pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/GlobalElementComplexTypeSequenceExtension when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

./xs:element[@name]/xs:complexType/xs:complexContent[xs:extension[@base]/xs:sequence]/
(../../(., @name), .., ., xs:extension/(., @base, xs:sequence/(.,
xs:element/(., @name), xs:attribute/(., @name))))

2.4 Global Attribute Declarations

2.4.1 GlobalAttributeUnqualifiedType

An [XML 1.0] document exhibits the GlobalAttributeUnqualifiedType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/GlobalAttributeUnqualifiedType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

./xs:attribute[@name and @type and not(contains(@type,
':'))]/ (., @name, @type)

2.5 Element Declarations

2.5.1 ElementMinOccursFinite

An [XML 1.0] document exhibits the ElementMinOccursFinite pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/ElementMinOccursFinite when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:element[xs:integer(@minOccurs) gt 1]/ (@minOccurs,
@maxOccurs)

The following example [XML Schema 1.0] extract illustrates the use of the ElementMinOccursFinite pattern within an [XML Schema 1.0] document [ElementMinOccurs2MaxOccurs2]:

<xs:element name="itemColors2" type="ex:ItemColors2" />
<xs:complexType name="ItemColors2">
  <xs:sequence>
    <xs:element name="itemColor" type="xs:string" minOccurs="2" maxOccurs="2" />
  </xs:sequence>
</xs:complexType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [ElementMinOccurs2MaxOccurs201]:

  <ex:itemColors2>
      <ex:itemColor>Red</ex:itemColor>
      <ex:itemColor>Yellow</ex:itemColor>
   </ex:itemColors2>

The following example [XML Schema 1.0] extract illustrates the use of the ElementMinOccursFinite pattern within an [XML Schema 1.0] document [ElementMinOccurs2orMore]:

<xs:element name="itemColors" type="ex:ItemColors" />
<xs:complexType name="ItemColors">
  <xs:sequence>
    <xs:element name="itemColor" type="xs:string" minOccurs="2" maxOccurs="unbounded" />
  </xs:sequence>
</xs:complexType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [ElementMinOccurs2orMore01]:

  <ex:itemColors>
      <ex:itemColor>Red</ex:itemColor>
      <ex:itemColor>Black</ex:itemColor>
      <ex:itemColor>White</ex:itemColor>
      <ex:itemColor>Yellow</ex:itemColor>
   </ex:itemColors>

as is the following element when included in an instance document [ElementMinOccurs2orMore02]:

  <ex:itemColors>
      <ex:itemColor>Black</ex:itemColor>
      <ex:itemColor>White</ex:itemColor>
   </ex:itemColors>

2.5.2 ElementMaxOccursFinite

An [XML 1.0] document exhibits the ElementMaxOccursFinite pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/ElementMaxOccursFinite when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:element[@maxOccurs and not(@maxOccurs = '0' or
@maxOccurs = '1' or @maxOccurs = 'unbounded')]/
(@maxOccurs)

The following example [XML Schema 1.0] extract illustrates the use of the ElementMaxOccursFinite pattern within an [XML Schema 1.0] document [ElementMaxOccursFinite]:

<xs:element name="summer" type="ex:Summer" />
<xs:complexType name="Summer">
  <xs:sequence>
    <xs:element name="mnth" type="xs:string" maxOccurs="4" />
  </xs:sequence>
</xs:complexType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [ElementMaxOccursFinite01]:

  <ex:summer>
      <ex:mnth>May</ex:mnth>
      <ex:mnth>June</ex:mnth>
      <ex:mnth>July</ex:mnth>
      <ex:mnth>August</ex:mnth>
   </ex:summer>

as is the following element when included in an instance document [ElementMaxOccursFinite02]:

  <ex:summer>
      <ex:mnth>August</ex:mnth>
      <ex:mnth>September</ex:mnth>
   </ex:summer>

2.5.3 AttributeElementNameClash

An [XML 1.0] document exhibits the AttributeElementNameClash pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/AttributeElementNameClash when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:complexType/xs:sequence/xs:element[@name =
../../xs:attribute/@name]/ (@name)

The following example [XML Schema 1.0] extract illustrates the use of the AttributeElementNameClash pattern within an [XML Schema 1.0] document [AttributeElementNameClash]:

<xs:element name="clientDetails" type="ex:ClientDetails" />
<xs:complexType name="ClientDetails">
  <xs:sequence>
    <xs:element name="forename" type="xs:string" />
    <xs:element name="surname" type="xs:string" />
    <xs:element name="title" type="xs:string" />
  </xs:sequence>
  <xs:attribute name="phone" type="xs:long" />
  <xs:attribute name="title" type="xs:boolean" />
</xs:complexType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [AttributeElementNameClash01]:

  <ex:clientDetails phone="0123456789" title="true">
      <ex:forename>Bobby</ex:forename>
      <ex:surname>Sox</ex:surname>
      <ex:title>Mr</ex:title>
   </ex:clientDetails>

2.5.4 NillableOptionalElement

An [XML 1.0] document exhibits the NillableOptionalElement pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/NillableOptionalElement when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:element[@nillable = 'true' and @minOccurs = '0']/
(@nillable, @minOccurs)

Note, this specification places no particular semantics on the difference between annotating an element with xsi:nil and the absence of an element.

The following example [XML Schema 1.0] extract illustrates the use of the NillableOptionalElement pattern within an [XML Schema 1.0] document [NillableOptionalElement]:

<xs:element name="nillableOptionalMiddleName" type="ex:NillableOptionalMiddleName" />
<xs:complexType name="NillableOptionalMiddleName">
  <xs:sequence>
    <xs:element name="firstName" type="xs:string" />
    <xs:element name="middleName" type="xs:string" minOccurs="0" nillable="true" />
    <xs:element name="lastName" type="xs:string" />
  </xs:sequence>
</xs:complexType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [NillableOptionalElement01]:

  <ex:nillableOptionalMiddleName>
      <ex:firstName>Paul</ex:firstName>
      <ex:lastName>Downey</ex:lastName>
   </ex:nillableOptionalMiddleName>

as is the following element when included in an instance document [NillableOptionalElement02]:

  <ex:nillableOptionalMiddleName>
      <ex:firstName>Paul</ex:firstName>
      <ex:middleName>Sumner</ex:middleName>
      <ex:lastName>Downey</ex:lastName>
   </ex:nillableOptionalMiddleName>

and the following element when included in an instance document [NillableOptionalElement03]:

  <ex:nillableOptionalMiddleName>
      <ex:firstName>Paul</ex:firstName>
      <ex:middleName xsi:nil="true"/>
      <ex:lastName>Downey</ex:lastName>
   </ex:nillableOptionalMiddleName>

2.5.5 ElementTypeReferenceUnqualified

An [XML 1.0] document exhibits the ElementTypeReferenceUnqualified pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/ElementTypeReferenceUnqualified when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:element[@name and @type and
namespace-uri-from-QName(resolve-QName(@type,.)) !=
'http://www.w3.org/2001/XMLSchema' and not(contains(@type, ':'))]/
(., @name, @type)

2.5.6 ElementReferenceUnqualified

An [XML 1.0] document exhibits the ElementReferenceUnqualified pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/ElementReferenceUnqualified when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:element[@ref and not(contains(@ref, ':'))]/ (.,
@ref)

2.6 Attribute Declarations

2.6.1 ElementDefault

An [XML 1.0] document exhibits the ElementDefault pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/ElementDefault when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:element[@default]/ (@default)

The following example [XML Schema 1.0] extract illustrates the use of the ElementDefault pattern within an [XML Schema 1.0] document [GlobalElementDefault]:

<xs:element name="globalElementDefault" type="xs:string" default="theDefaultValue" />

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [GlobalElementDefault01]:

  <ex:globalElementDefault/>

as is the following element when included in an instance document [GlobalElementDefault02]:

  <ex:globalElementDefault>theDefaultValue</ex:globalElementDefault>

and the following element when included in an instance document [GlobalElementDefault03]:

  <ex:globalElementDefault>anotherValue</ex:globalElementDefault>

The following example [XML Schema 1.0] extract illustrates the use of the ElementDefault pattern within an [XML Schema 1.0] document [LocalElementDefault]:

<xs:element name="localElementDefault" type="ex:LocalElementDefault" />
<xs:complexType name="LocalElementDefault">
  <xs:sequence>
    <xs:element name="text" type="xs:string" minOccurs="0" default="theDefaultValue" />
  </xs:sequence>
</xs:complexType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [LocalElementDefault01]:

  <ex:localElementDefault/>

as is the following element when included in an instance document [LocalElementDefault02]:

  <ex:localElementDefault>
      <ex:text/>
   </ex:localElementDefault>

and the following element when included in an instance document [LocalElementDefault03]:

  <ex:localElementDefault>
      <ex:text>theDefaultValue</ex:text>
   </ex:localElementDefault>

and the following element when included in an instance document [LocalElementDefault04]:

  <ex:localElementDefault>
      <ex:text>anotherValue</ex:text>
   </ex:localElementDefault>

2.6.2 AttributeRequired

An [XML 1.0] document exhibits the AttributeRequired pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/AttributeRequired when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:attribute[@use = 'required']/ (@use)

The following example [XML Schema 1.0] extract illustrates the use of the AttributeRequired pattern within an [XML Schema 1.0] document [AttributeRequired]:

<xs:element name="discount" type="ex:Discount" />
<xs:complexType name="Discount">
  <xs:sequence>
    <xs:element name="percentage" type="xs:int" />
  </xs:sequence>
  <xs:attribute name="id" type="xs:string" />
  <xs:attribute name="seasonal" type="xs:boolean" use="required" />
</xs:complexType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [AttributeRequired01]:

  <ex:discount id="1611" seasonal="true">
      <ex:percentage>5</ex:percentage>
   </ex:discount>

as is the following element when included in an instance document [AttributeRequired02]:

  <ex:discount id="1612" seasonal="false">
      <ex:percentage>2</ex:percentage>
   </ex:discount>

2.6.3 AttributeFixed

An [XML 1.0] document exhibits the AttributeFixed pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/AttributeFixed when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:attribute[@fixed] / (@fixed)

The following example [XML Schema 1.0] extract illustrates the use of the AttributeFixed pattern within an [XML Schema 1.0] document [AttributeFixed]:

<xs:element name="survey" type="ex:Survey" />
<xs:complexType name="Survey">
  <xs:sequence>
    <xs:element name="fee" type="xs:int" />
  </xs:sequence>
  <xs:attribute name="id" type="xs:string" />
  <xs:attribute name="currency" type="xs:string" fixed="GBP" />
</xs:complexType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [AttributeFixed01]:

  <ex:survey id="1511" currency="GBP">
      <ex:fee>500</ex:fee>
   </ex:survey>

2.6.4 AttributeDefault

An [XML 1.0] document exhibits the AttributeDefault pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/AttributeDefault when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:attribute[@default] / (@default)

The following example [XML Schema 1.0] extract illustrates the use of the AttributeDefault pattern within an [XML Schema 1.0] document [AttributeDefault]:

<xs:element name="attributeDefault" type="ex:AttributeDefault" />
<xs:complexType name="AttributeDefault">
  <xs:sequence>
    <xs:element name="text" type="xs:string" minOccurs="0" />
  </xs:sequence>
  <xs:attribute name="defaultedValue" type="xs:string" default="theDefaultValue" />
</xs:complexType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [AttributeDefault01]:

  <ex:attributeDefault/>

as is the following element when included in an instance document [AttributeDefault02]:

  <ex:attributeDefault defaultedValue="theDefaultValue"/>

and the following element when included in an instance document [AttributeDefault03]:

  <ex:attributeDefault defaultedValue=""/>

and the following element when included in an instance document [AttributeDefault04]:

  <ex:attributeDefault defaultedValue="anotherValue"/>

2.6.5 AttributeReferenceUnqualified

An [XML 1.0] document exhibits the AttributeReferenceUnqualified pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/AttributeReferenceUnqualified when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:attribute[@ref and not(contains(@ref, ':'))]/ (.,
@ref)

2.6.6 AttributeTypeReferenceUnqualified

An [XML 1.0] document exhibits the AttributeTypeReferenceUnqualified pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/AttributeTypeReferenceUnqualified when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:attribute[@name and @type and
namespace-uri-from-QName(resolve-QName(@type,.)) !=
'http://www.w3.org/2001/XMLSchema' and not(contains(@type, ':'))]/
(., @name, @type)

2.6.7 LocalAttributeSimpleType

An [XML 1.0] document exhibits the LocalAttributeSimpleType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/LocalAttributeSimpleType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:attribute[not(parent::xs:schema)]/xs:simpleType

2.7 SimpleType Declarations

2.7.1 NMTOKENEnumerationType

An [XML 1.0] document exhibits the NMTOKENEnumerationType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/NMTOKENEnumerationType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:simpleType/xs:restriction[@base/resolve-QName(.,..) =
xs:QName('xs:NMTOKEN') and xs:enumeration]/ (., @base,
xs:enumeration/(., @value))

The following example [XML Schema 1.0] extract illustrates the use of the NMTOKENEnumerationType pattern within an [XML Schema 1.0] document [NMTOKENEnumerationType]:

<xs:element name="nMTOKENEnumerationType" type="ex:NMTOKENEnumerationType" />
<xs:simpleType name="NMTOKENEnumerationType">
  <xs:restrictionbase="xs:NMTOKEN">
    <xs:enumerationvalue="token1" />
    <xs:enumerationvalue="token2" />
    <xs:enumerationvalue="token3" />
  </xs:restriction>
</xs:simpleType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [NMTOKENEnumerationType01]:

  <ex:nMTOKENEnumerationType>token1</ex:nMTOKENEnumerationType>

2.7.2 IntEnumerationType

An [XML 1.0] document exhibits the IntEnumerationType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/IntEnumerationType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:simpleType/xs:restriction[@base/resolve-QName(.,..) =
xs:QName('xs:int') and xs:enumeration]/ (., @base,
xs:enumeration/(., @value))

The following example [XML Schema 1.0] extract illustrates the use of the IntEnumerationType pattern within an [XML Schema 1.0] document [IntEnumerationType]:

<xs:element name="intEnumerationType" type="ex:IntEnumerationType" />
<xs:simpleType name="IntEnumerationType">
  <xs:restrictionbase="xs:int">
    <xs:enumerationvalue="2" />
    <xs:enumerationvalue="3" />
    <xs:enumerationvalue="5" />
    <xs:enumerationvalue="7" />
  </xs:restriction>
</xs:simpleType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [IntEnumerationType01]:

  <ex:intEnumerationType>2</ex:intEnumerationType>

2.7.3 ShortEnumerationType

An [XML 1.0] document exhibits the ShortEnumerationType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/ShortEnumerationType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:simpleType/xs:restriction[@base/resolve-QName(.,..) =
xs:QName('xs:short') and xs:enumeration]/ (., @base,
xs:enumeration/(., @value))

The following example [XML Schema 1.0] extract illustrates the use of the ShortEnumerationType pattern within an [XML Schema 1.0] document [ShortEnumerationType]:

<xs:element name="shortEnumerationType" type="ex:ShortEnumerationType" />
<xs:simpleType name="ShortEnumerationType">
  <xs:restrictionbase="xs:short">
    <xs:enumerationvalue="7" />
    <xs:enumerationvalue="11" />
    <xs:enumerationvalue="13" />
  </xs:restriction>
</xs:simpleType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [ShortEnumerationType01]:

  <ex:shortEnumerationType>11</ex:shortEnumerationType>

2.7.4 LongEnumerationType

An [XML 1.0] document exhibits the LongEnumerationType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/LongEnumerationType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:simpleType/xs:restriction[@base/resolve-QName(.,..) =
xs:QName('xs:long') and xs:enumeration]/ (., @base,
xs:enumeration/(., @value))

The following example [XML Schema 1.0] extract illustrates the use of the LongEnumerationType pattern within an [XML Schema 1.0] document [LongEnumerationType]:

<xs:element name="longEnumerationType" type="ex:LongEnumerationType" />
<xs:simpleType name="LongEnumerationType">
  <xs:restrictionbase="xs:long">
    <xs:enumerationvalue="9152052" />
    <xs:enumerationvalue="7816230" />
    <xs:enumerationvalue="7235733" />
  </xs:restriction>
</xs:simpleType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [LongEnumerationType01]:

  <ex:longEnumerationType>9152052</ex:longEnumerationType>

2.7.5 DoubleEnumerationType

An [XML 1.0] document exhibits the DoubleEnumerationType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/DoubleEnumerationType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:simpleType/xs:restriction[@base/resolve-QName(.,..) =
xs:QName('xs:double') and xs:enumeration]/ (., @base,
xs:enumeration/(., @value))

The following example [XML Schema 1.0] extract illustrates the use of the DoubleEnumerationType pattern within an [XML Schema 1.0] document [DoubleEnumerationType]:

<xs:element name="doubleEnumerationType" type="ex:DoubleEnumerationType" />
<xs:simpleType name="DoubleEnumerationType">
  <xs:restrictionbase="xs:double">
    <xs:enumerationvalue="1267.43233E12" />
    <xs:enumerationvalue="7234.34541E12" />
    <xs:enumerationvalue="5733.65565E12" />
  </xs:restriction>
</xs:simpleType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [DoubleEnumerationType01]:

  <ex:doubleEnumerationType>1267.43233E12</ex:doubleEnumerationType>

2.7.6 IntegerEnumerationType

An [XML 1.0] document exhibits the IntegerEnumerationType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/IntegerEnumerationType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:simpleType/xs:restriction[@base/resolve-QName(.,..) =
xs:QName('xs:integer') and xs:enumeration]/ (., @base,
xs:enumeration/(., @value))

The following example [XML Schema 1.0] extract illustrates the use of the IntegerEnumerationType pattern within an [XML Schema 1.0] document [IntegerEnumerationType]:

<xs:element name="integerEnumerationType" type="ex:IntegerEnumerationType" />
<xs:simpleType name="IntegerEnumerationType">
  <xs:restrictionbase="xs:integer">
    <xs:enumerationvalue="4000000" />
    <xs:enumerationvalue="5000000" />
    <xs:enumerationvalue="6000000" />
  </xs:restriction>
</xs:simpleType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [IntegerEnumerationType01]:

  <ex:integerEnumerationType>4000000</ex:integerEnumerationType>

2.7.7 DecimalEnumerationType

An [XML 1.0] document exhibits the DecimalEnumerationType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/DecimalEnumerationType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:simpleType/xs:restriction[@base/resolve-QName(.,..) =
xs:QName('xs:decimal') and xs:enumeration]/ (., @base,
xs:enumeration/(., @value))

The following example [XML Schema 1.0] extract illustrates the use of the DecimalEnumerationType pattern within an [XML Schema 1.0] document [DecimalEnumerationType]:

<xs:element name="decimalEnumerationType" type="ex:DecimalEnumerationType" />
<xs:simpleType name="DecimalEnumerationType">
  <xs:restrictionbase="xs:decimal">
    <xs:enumerationvalue="+1000.0001" />
    <xs:enumerationvalue="-1000.0001" />
    <xs:enumerationvalue="1000.0002" />
  </xs:restriction>
</xs:simpleType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [DecimalEnumerationType01]:

  <ex:decimalEnumerationType>1000.0002</ex:decimalEnumerationType>

2.7.8 FloatEnumerationType

An [XML 1.0] document exhibits the FloatEnumerationType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/FloatEnumerationType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:simpleType/xs:restriction[@base/resolve-QName(.,..) =
xs:QName('xs:float') and xs:enumeration]/ (., @base,
xs:enumeration/(., @value))

The following example [XML Schema 1.0] extract illustrates the use of the FloatEnumerationType pattern within an [XML Schema 1.0] document [FloatEnumerationType]:

<xs:element name="floatEnumerationType" type="ex:FloatEnumerationType" />
<xs:simpleType name="FloatEnumerationType">
  <xs:restrictionbase="xs:float">
    <xs:enumerationvalue="1267.43233E12" />
    <xs:enumerationvalue="7234.34541E12" />
    <xs:enumerationvalue="5733.65565E12" />
  </xs:restriction>
</xs:simpleType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [FloatEnumerationType01]:

  <ex:floatEnumerationType>1267.43233E12</ex:floatEnumerationType>

2.7.9 NonNegativeIntegerEnumerationType

An [XML 1.0] document exhibits the NonNegativeIntegerEnumerationType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/NonNegativeIntegerEnumerationType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:simpleType/xs:restriction[@base/resolve-QName(.,..) =
xs:QName('xs:nonNegativeInteger') and xs:enumeration]/ (., @base,
xs:enumeration/(., @value))

The following example [XML Schema 1.0] extract illustrates the use of the NonNegativeIntegerEnumerationType pattern within an [XML Schema 1.0] document [NonNegativeIntegerEnumerationType]:

<xs:element name="nonNegativeIntegerEnumerationType" type="ex:NonNegativeIntegerEnumerationType" />
<xs:simpleType name="NonNegativeIntegerEnumerationType">
  <xs:restrictionbase="xs:nonNegativeInteger">
    <xs:enumerationvalue="12" />
    <xs:enumerationvalue="24" />
    <xs:enumerationvalue="33" />
  </xs:restriction>
</xs:simpleType>

The following example [XML 1.0] element is valid against the above example [XML Schema 1.0] when included inside an instance document [NonNegativeIntegerEnumerationType01]:

  <ex:nonNegativeIntegerEnumerationType>12</ex:nonNegativeIntegerEnumerationType>

2.7.10 PositiveIntegerEnumerationType

An [XML 1.0] document exhibits the PositiveIntegerEnumerationType pattern identified using the URI [RFC 3986] http://www.w3.org/2002/ws/databinding/patterns/6/09/PositiveIntegerEnumerationType when the following [XPath 2.0] expression applied to a document or element node located by //xs:schema results in an [XPath 2.0] node-set containing at least one node:

.//xs:simpleType/xs:restriction[@base/resolve-QName(.,..) =
xs:QName('xs:positiveInteger') and xs:enumeration]/ (., @base,
xs:enumeration/(., @value))

The following example [XML Schema 1.0] extract illustrates the use of the PositiveIntegerEnumerationType pattern within an [XML Schema 1.0] document [PositiveIntegerEnumerationType]:

<xs:element name="positiveIntegerEnumerationType" type="ex:PositiveIntegerEnumerationType" />
<xs:simpleType name="PositiveIntegerEnumerationType">
  <xs:restrictionbase="xs:positiveInteger">
    <xs:enumerationvalue="12" />
    <xs:enumerationvalue="24" />
    <xs:enumerationvalue="33" />
  </