Order Indicators
Order indicators define the order or sequence in which child elements can occur in an XML document. The following table lists the order indicators.

Indicator Description Example
sequence
Specifies that the complexType element must contain child elements, and the child elements must appear in the specified order

    <xs:element name="EmpName">
      <xs:complexType>
        <xs:sequence>
           <xs:element name="firstname" type="xs:string"/>            <xs:element name="lastname" type="xs:string"/>
        </xs:sequence>
      </xs:complexType>
    </xs:element>

The EmpName element must contain firstname and lastname elements, and the firstname element must appear before the lastname element.
all
Specifies that the complexType element can contain child elements in any order, and the child elements must occur only once

    <xs:element name="DeptID">
      <xs:complexType>
        <xs:all>
           <xs:element
      name="DeptNumber" type="xs:string"/>
           <xs:element name="LocationID"
      type="xs:string"/>
        </xs:all>
      </xs:complexType>
    </xs:element>

The DeptID element must contain DeptNumber and LocationID elements in any order, and the child elements must appear only once.
choice
Specifies that the complexType element can contain either of the two child elements

    <xs:element name="Employee">
      <xs:complexType>
        <xs:choice>
          <xs:element name="permanent" type="xs:string"/>
     
<xs:element name="temporary" type="xs:string"/>
        </xs:choice>
      </xs:complexType>
    </xs:element>

The Employee element must contain either the permanent or temporary element.

 

Click the Next button to continue.