XML in a Nutshell, 3rd Edition

Name

xsi:noNamespaceSchemaLocation

Synopsis

The xsi:noNamespaceSchemaLocation attribute locates the schema for elements that are not in any namespace. (Attributes that are not in any namespace are assumed to be declared in the same schema as their parent element.) Its value is a relative or absolute URL where the schema document can be found. It is most commonly attached to the root element but can appear further down the tree. For example, this person element claims that it should be validated against the schema found at http://example.com/person.xsd:

<person xsi:noNamespaceSchemaLocation="http://example.com/person.xsd">
  <name>
    <first_name>Alan</first_name>
    <last_name>Turing</last_name>
  </name>
  <profession>computer scientist</profession>
  <profession>mathematician</profession>
  <profession>cryptographer</profession>
</person>

These are only suggestions. Schema processors may use other means of locating the relevant schemas and ignore the hint provided by xsi:noNamespaceSchemaLocation.