title: Using Oracle XMLTABLE to get attribute value
body: <pre><code>&lt;PivotSet&gt;
  &lt;item&gt;
  &lt;column name = "B"&gt;A&lt;/column&gt;
  &lt;column name ="SUM(A)"&gt;24&lt;/column&gt;
  &lt;/item&gt;
  &lt;item&gt;
  &lt;column name = "B"&gt;B&lt;/column&gt;
  &lt;column name = "SUM(A)"&gt;15&lt;/column&gt;
  &lt;/item&gt;
  &lt;item&gt;
  &lt;column name = "B"&gt;C&lt;/column&gt;
  &lt;column name = "SUM(A)"&gt;18&lt;/column&gt;
  &lt;/item&gt;
  &lt;item&gt;
  &lt;column name = "B"&gt;D&lt;/column&gt;
  &lt;column name = "SUM(A)"&gt;21&lt;/column&gt;
  &lt;/item&gt;
  &lt;/PivotSet&gt;
  </code></pre>
  
  <p>I have this XML column. Im trying to read the value A in the XML tag </p>
  
  <pre><code>&lt;column name = "B"&gt;A&lt;/column&gt;
  </code></pre>
  
  <p>Below SQL generates the above XML.</p>
  
  <pre><code>select xmlserialize(content t.B_XML) from t_aa
  pivot xml(
  sum(A) for B in (any)
  ) t;
  </code></pre>
  
  <p>Can you please help me with XMLTABLE SQL for this</p>