pattern 

The required pattern attribute is a reference to a pattern that is
active in the current phase.

Attribute Information

Used By

Element sch:active

Source 

<xs:attribute name="pattern" use="required" type="xs:IDREF">
  <xs:annotation>
    <xs:documentation>The required pattern attribute is a reference to a pattern that is active in the current phase.</xs:documentation>
  </xs:annotation>
</xs:attribute>

Sample