| Element | 
    Explanation | 
  
  
    | all | 
    Specifies that the child elements can appear in any order. Each child 
    element can occur 0 or 1 time | 
  
  
    | annotation | 
    Specifies the top-level element for schema comments | 
  
  
    | any | 
    Enables the author to extend the XML document with elements 
    not specified by the schema | 
  
  
    | anyAttribute | 
    
 Enables the author to extend the XML document with attributes not specified 
by the schema 
     | 
  
  
    | appinfo | 
    Specifies information to be used by the application (must 
    go inside annotation) | 
  
  
    | attribute | 
    Defines an attribute | 
  
  
    | attributeGroup | 
    Defines an attribute group to be used in complex type 
    definitions | 
  
  
    | choice | 
    Allows only one of the elements contained in the <choice> 
    declaration to be present within the containing element | 
  
  
    | complexContent | 
    Defines extensions or restrictions on a complex type that 
    contains mixed content or elements only | 
  
  
    | complexType | 
    Defines a complex type element | 
  
  
    | documentation | 
    Defines text comments in a schema (must go inside 
    annotation) | 
  
  
    | element | 
    Defines an element | 
  
  
    | extension | 
    Extends an existing simpleType or complexType element | 
  
  
    | field | 
    Specifies an XPath expression that specifies the value used 
    to define an identity constraint | 
  
  
    | group | 
    Defines a group of elements to be used in complex type 
    definitions | 
  
  
    | import | 
    Adds multiple schemas with different target 
    namespace to a document | 
  
  
    | include | 
    Adds multiple schemas with the same target 
    namespace to a document | 
  
  
    | key | 
    Specifies an attribute or element value as a 
    key (unique, non-nullable, and always present) within the containing element 
    in an instance document | 
  
  
    | keyref | 
    Specifies that an attribute or element value correspond to 
    those of the specified key or unique element | 
  
  
    | list | 
    Defines a simple type element as a list of values | 
  
  
    | notation | 
    Describes the format of non-XML data within an XML document | 
  
  
    | redefine | 
    Redefines simple and complex types, groups, and attribute 
    groups from an external schema | 
  
  
    | restriction | 
    Defines restrictions on a simpleType, simpleContent, or a 
    complexContent | 
  
  
    | schema | 
    Defines the root element of a schema | 
  
  
    | selector | 
    Specifies an XPath expression that selects a set of 
    elements for an identity constraint | 
  
  
    | sequence | 
    Specifies that the child elements must appear in a sequence. Each child 
    element can occur from 0 to any number of times | 
  
  
    | simpleContent | 
    Contains extensions or restrictions on a text-only complex type or on a simple type as content and contains no elements | 
  
  
    | simpleType | 
    Defines a simple type and specifies the constraints and 
    information about the values of attributes or text-only elements | 
  
  
    | union | 
    Defines a simple type as a collection (union) of values 
    from specified simple data types | 
  
  
    | unique | 
    Defines that an element or an attribute value must be 
    unique within the scope | 
  
  
    | Constraint | 
    Description | 
  
  
    | enumeration | 
    Defines a list of acceptable values | 
  
  
    | fractionDigits | 
    Specifies the maximum number of decimal places allowed. 
    Must be equal to or greater than zero | 
  
  
    | length | 
    Specifies the exact number of characters or list items 
    allowed. Must be equal to or greater than zero | 
  
  
    | maxExclusive | 
    Specifies the upper bounds for numeric values (the value 
    must be less than this value) | 
  
  
    | maxInclusive | 
    Specifies the upper bounds for numeric values (the value 
    must be less than or equal to this value) | 
  
  
    | maxLength | 
    Specifies the maximum number of characters or list items 
    allowed. Must be equal to or greater than zero | 
  
  
    | minExclusive | 
    Specifies the lower bounds for numeric values (the value 
    must be greater than this value) | 
  
  
    | minInclusive | 
    Specifies the lower bounds for numeric values (the value 
    must be greater than or equal to this value) | 
  
  
    | minLength | 
    Specifies the minimum number of characters or list items 
    allowed. Must be equal to or greater than zero | 
  
  
    | pattern | 
    Defines the exact sequence of characters that are 
    acceptable  | 
  
  
    | totalDigits | 
    Specifies the maximum number of digits allowed. Must be 
    greater than zero | 
  
  
    | whiteSpace | 
    Specifies how white space (line feeds, tabs, spaces, and 
    carriage returns) is handled |