xs:element

Purpose	This element allows you to define elements. If the `xs:element` element is the child element of an `xs:schema` element, it defines a global element and the `name` attribute is required. If the `xs:element` element is the descendant element of a `xs:complexType` element, its `name` attribute performs a definition of local elements.
Parent element	`xs:all`, `xs:choice`, `xs:group`, `xs:sequence`, `xs:schema`
Child elements	`xs:annotation`, `xs:complexType`, `xs:key`, `xs:keyref`, `xs:simpleType`, `xs:unique`
Attributes	`abstract` (global elements only), `default`, `final` (global elements only), `fixed`, `form` (only if not below `xs:schema`), `maxOccurs` (only if not below `xs:schema`), `minOccurs` (only if not below `xs:schema`), `name`, `nillable`, `ref` (only if not below `xs:schema`), `substitutionGroup` (global elements only), `type`

Attributes

Name	Type	Description
`abstract`	`xs:boolean`	If "true", this element declaration must not be used for validation. Typically, another element from the substitution group will be used in an XML document.
`block`	`xs:boolean`	This attribute, in conjunction with the schema's `blockDefault` attribute (if `block` is not specified, the `blockDefault` attribute value takes effect), is used at validation time. It specifies the types that can be used in an xsi:type attribute or the types of a substituting element that can be used in an element that is validated against the current element declaration. The value is a whitespace-separated list of: restriction The alternate type definition is not allowed to be derived by restriction from the default type defined by this element declaration. extension The alternate type definition is not allowed to be derived by extension from the default type defined by this element declaration. substitution Substitution by a member of the substitution group is not allowed. Alternatively, the value "#all" can be specified. This prevents the substitution of an element that is validated against this element declaration.
`default`	`xs:string`	Allows you to specify for an element a default value that is inserted if the element occurs with empty content in the XML instance. Note: The `default` attribute may not be used together with the `fixed` attribute.
`final`		This attribute, in conjunction with the schema's `finalDefault` attribute (if `final` is not specified, the `finalDefault` attribute value takes effect), is used when performing schema checks. It specifies the substitutions that are valid for an element that is validated against the current element declaration. The value is a whitespace-separated list of: substitution No substitution is allowed. restriction Substitution by an element whose datatype is derived from the current element's datatype by restriction is not allowed. extension Substitution by an element whose datatype is derived from the current element's datatype by extension is not allowed. Alternatively, the special value "#all" can be specified. This also means that no substitution is allowed.
`fixed`	`xs:string`	Specifies the value that the element that must have if present. This has the following consequences for instances of that schema: Element present in instance: The value of the element must either match the value of the `fixed` attribute or be empty. If empty, Tamino inserts the value of the `fixed` attribute into the element. Element not present in instance: Tamino does not insert the element or any value into the XML instance. Note: The `fixed` attribute may not be used together with the `default` attribute.
`form`	`xs:NMTOKEN`	Determines whether the occurrence of locally-declared elements in an instance document must be qualified by a namespace specification. It overrides the default that is set by the `elementFormDefault` attribute of the `xs:schema` element. It can have the value "qualified" or "unqualified". The default is "unqualified".
`maxOccurs`	`xs:nonNegativeInteger` or "unbounded"	Together with the `minOccurs` attribute described above, this attribute expresses multiplicity in TSD (and XML Schema) element definitions. The value of a `maxOccurs` attribute in an `xs:element` declaration determines the maximum number of occurrences of a specific element. The value of `maxOccurs` must be a non-negative integer or the value "unbounded". The default value for `maxOccurs` is 1.
`minOccurs`	`xs:nonNegativeInteger`	Together with the `maxOccurs` attribute described below, this attribute expresses multiplicity in TSD (and XML Schema) element definitions. The value of a `minOccurs` attribute in an `xs:element` declaration determines the minimum number of occurrences of a specific element. The value of `minOccurs` must be a non-negative integer. The default value for `minOccurs` is 1.
`name`	`xs:NCName`	Specifies a name for the element. Note: The `name` and `ref` attributes are mutually exclusive.
`nillable`	`xs:boolean`	If "true", an instance to be validated against this element may have an additional `xsi:nil` attribute. If `xsi:nil="true"`, the element must not have any content: neither text nor child nodes. The validation of attributes is not affected. (See section 2.9 Nil Values in the W3C documentation XML Schema Part 0: Primer.) Default value: "false". Tamino-Specific Constraints An element or a descendant of an element with `nillable="true"` must not be referenced in a tsd:unique constraint.
`ref`	`xs:QName`	A global element can be referenced in other declarations in the same schema using the `ref` attribute of the `xs:element` element. The value of the `ref` attribute must refer to a global element. Only the `minOccurs` and `maxOccurs` attributes are allowed in conjunction with the `ref` attribute For more information, refer to the subsection 2.2 Complex Type Definitions, Element & Attribute Declarations in W3C´s document XML Schema Part 0: Primer Note: The `name` and `ref` attributes are mutually exclusive.
`substitutionGroup`	`xs:QName`	Refers to a global element declaration with a matching QName. The referenced element declaration is called the substitution group head element. This is an element that is valid against the current element declaration (which must be a global declaration), then it is a valid replacement for any element validated against the substitution group head element. See section 4.6 Substitution Groups in the W3C documentation XML Schema Part 0: Primer.
`type`	`xs:QName`	Indicates the type of the element to be defined. The type can be any of the predefined types described in section 3 Built-in datatypes of W3C Recommendation, XML Schema Part 2: Datatypes or any user-defined type. The occurrence of the `type` attribute and the occurrence of the `xs:simpleType` and `xs:complexType` child elements are mutually exclusive. The type can be either a simple or a complex type. Simple types are defined with the `xs:simpleType` element; complex types are defined with the `xs:complexType` element.

Example (using a complex type definition)

This example of an element definition using a complex type definition is taken from an XML Schema for a book store. It describes how an attribute Category is defined that can only have the values:

autobiography
non-fiction
fiction

      <xs:element name="Book">
        <xs:complexType>
          <xs:attribute name="Category" use="required">
            <xs:restriction>
              <xs:simpleType base="xs:string">
                <xs:enumeration value="autobiography"/>
                <xs:enumeration value="non-fiction"/>
                <xs:enumeration value="fiction"/>
              </xs:simpleType>
            </xs:restriction>
          </xs:attribute>
          <xs:attribute name="InStock" type="xs:boolean" use="optional" default="false"/>
          <xs:attribute name="Reviewer" type="xs:string" use="optional" default=""/>
        </xs:complexType>
      </xs:element>