XML namespaces and attributes

<bar xmlns:foo="http://www.foo.com/"
    foo:baz="baz"
    qux="qux"/>
<bar xmlns="http://www.foo.com/" xmlns:foo="http://www.foo.com/"
    foo:baz="baz"
    qux="qux"/>
<foo:bar xmlns="http://www.foo.com/" xmlns:foo="http://www.foo.com/"
    foo:baz="baz"
    qux="qux"/>

<{}bar
    {http://www.foo.com/}baz="baz"
    {}qux="qux"/>
<{http://www.foo.com/}bar
    {http://www.foo.com/}baz="baz"
    {}qux="qux"/>
<{http://www.foo.com/}bar
    {http://www.foo.com/}baz="baz"
    {}qux="qux"/>

<?xml version="1.0" encoding="utf-8"?>
<xs:schema  xmlns="http://schemas.mycompany.com/Customer/V1"
targetNamespace="http://schemas.mycompany.com/Customer/V1"
xmlns:xs="http://www.w3.org/2001/XMLSchema">

<xs:attribute name="Id" type="xs:positiveInteger"/>

<xs:element name="Customer">
   <xs:complexType>
      <xs:attribute ref="Id" use="required"/>
      <!-- some elements here -->
    </xs:complexType>
</xs:element>

<?xml version="1.0" encoding="utf-8"?>
<Customer Id="1" xmlns="http://schemas.mycompany.com/Customer/V1">
  <!-- ... other elements here -->
</Customer>

<?xml version="1.0" encoding="utf-8"?>
<Customer cus:Id="1" xmlns="http://schemas.mycompany.com/Customer/V1"
 xmlns:cus="http://schemas.mycompany.com/Customer/V1">
  <!-- ... other elements here -->
</Customer>

<xs:element name="Customer">
   <xs:complexType>
       <xs:attribute name="Id" type="xs:positiveInteger" use="required"/>
       <!-- some elements here -->
   </xs:complexType>
</xs:element>