Basic XML Schema Declarations

An XML Schema document is built of a series of declarations, which gives very detailed information and makes sure the information contained in the XML document is in the correct form.

Declaration Name	Purpose	Syntax
Schema	Identifies the language the schema uses	<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
Element	Defines an element	<xsd:element name="name">
Attribute	Defines an attribute	<xsd:attribute name="name" type="type">
Complex type	Defines an element that contains other elements, contains attributes, or contains mixed content (elements and text)	<xsd:complexType>
Simple type	Creates a constrained datatype for an element or attribute value	<xsd:simpleType>
Sequence compositor	Specifies that attributes or elements within a complex type must be listed in order	<xsd:sequence>
Choice compositor	Specifies that any one of the attributes or elements within a complex type can be used	<xsd:choice>
All compositor	Specifies that any or all attributes or elements within a complex type can be used	<xsd:all>
Annotation	Contains documentation and/or appInfo elements that provide additional information and comments about the schema document	<xsd:annotation>
Documentation	Provides human-readable information within an annotation	<xsd:documentation>
Application information	Provides computer-readable information within an annotation	<xsd:appInfo>

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