XPath expression to count unique child attributes
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I am writing an XPath expression to count unique child attribues. Using the following xPath expression I could fetch all the child attributes along with which are not unique:

    //*[count(*)=0] 

I need an XPath expression to return me all the unique attributes and the count of number of unique attributes

Eg: XML file

    <details>
        <Employee>
			<EmpNo>10</EmpNo>
            <EmpName>TestName</EmpName>
            <Address>
               <Address1>market</Address1>
               <Address2>motel</Address2>
			   <Street/>
            </Address>
		</Employee>
		
		<Employee>
			<EmpNo>20</EmpNo>
            <EmpName>TestName2</EmpName>
            <Address>
               <Address1>school</Address1>
               <Address2>playground</Address2>
			   <Street>
					<StreetName>TestStreet2</StreetName>
					<StreetCode>200</StreetCode>
			   </Street>
            </Address>
		</Employee>
  </details>

Expected output:

  

      <!-- Unique element's count -->
      <data>6</data>
      <!-- Unique Element Names -->
      <data>EmpNo</data>
      <data>EmpName</data>
      <data>Address1</data>
      <data>Address2</data>
      <data>StreetName</data>
      <data>StreetCode</data>
      <!-- Unique Element values -->
      <!-- Data Set 1 -->
      <data>10</data>
      <data>TestName</data>
      <data>market</data>
      <data>motel</data>
      <data>null</data>
      <data>null</data>
      <!-- Data Set 2 -->
      <data>20</data>
      <data>TestName2</data>
      <data>school</data>
      <data>playground</data>
      <data>TestStreet2</data>
      <data>200</data>


Thanks.