XML/XML Schema/length
xs:length defines a fixed length measured in number of characters or bytes (xs:hexBinary and xs:base64Binary)
<?xml version="1.0"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
targetNamespace="http://www.wbex.ru" xmlns="http://www.wbex.ru"
elementFormDefault="qualified">
<xs:simpleType name="standardNotations">
<xs:restriction base="xs:NOTATION">
<xs:length value="8" />
</xs:restriction>
</xs:simpleType>
</xs:schema>