title: How to remove duplicate elements from an xml file?
body: <p>I have an XML file like</p>
  
  <pre><code>&lt;ns0:Employees xmlns:ns0="http://TestIndexMap.Employees"&gt;
    &lt;Employee FirstName="FirstName_0" LastName="LastName_1" dept="dept_2" empNumber="1"&gt;
      &lt;Schedules&gt;
        &lt;Schedule Date_join="2008-01-20" Date_end="2008-01-30" /&gt;
      &lt;/Schedules&gt;
    &lt;/Employee&gt;
    &lt;Employee FirstName="FirstName_0" LastName="LastName_1" dept="dept_2" empNumber="2"&gt;
      &lt;Schedules&gt;
        &lt;Schedule Date_join="2008-01-20" Date_end="2008-01-30" /&gt;
      &lt;/Schedules&gt;
    &lt;/Employee&gt;
    &lt;Employee FirstName="FirstName_2" LastName="LastName_1" dept="dept_2" empNumber="2"&gt;
      &lt;Schedules&gt;
        &lt;Schedule Date_join="2007-01-21" Date_end="2007-12-30" /&gt;
  
      &lt;/Schedules&gt;
    &lt;/Employee&gt;
    &lt;Employee FirstName="FirstName_2" LastName="LastName_1" dept="dept_2" empNumber="2"&gt;
      &lt;Schedules&gt;
        &lt;Schedule Date_join="2007-01-21" Date_end="2007-12-30" /&gt;
        &lt;Schedule Date_join="2008-06-20" Date_end="2008-01-30" /&gt;
  
      &lt;/Schedules&gt;
    &lt;/Employee&gt;
  &lt;/ns0:Employees&gt;
  </code></pre>
  
  <p>I would want to remove the duplicates based on the fistname, last name and date_join and data_end . </p>
  
  <p>Please, can someone explain how to achive this with XSLT?</p>