@BNV,  below SQL code worked for me, I'm able to extract Red for colID=10

select
  xpath(
    '''
    <XMLData>
    <Values>
    <ValueDefinition colID="10" Value="Red"/>
    <ValueDefinition colID="20" Value="Square"/>
    <ValueDefinition colID="3" Value=""/>
    </Values>
    </XMLData>''',
    '//ValueDefinition[@colID="10"]/@Value'
  )[0] as value