XML Tutorial/XML Schema/int

specifies a sequence of zero to nine digits

<!-- schema -->
<xsd:element name="ninedigits">
  <xsd:simpleType>
   <xsd:restriction base="xsd:int">
    <xsd:pattern value="\d{0,9}"/>
   </xsd:restriction>
  </xsd:simpleType>
</xsd:element>
<!-- instance document -->
<ninedigits>217748364</ninedigits>

The int data type is derived from the long type.

The value space is integer values from ?47483648 up to and including 2147483647. 
The lexical space is a finite-length sequence of decimal digits with an optional leading - or +.
<!-- schema -->
<xsd:element name="ninedigits">
  <xsd:simpleType>
   <xsd:restriction base="xsd:int">
    <xsd:totalDigits value="9"/>
   </xsd:restriction>
  </xsd:simpleType>
</xsd:element>
<!-- instance document -->
<ninedigits>217748364</ninedigits>