title: Oracle: how to add a text node into an existing element
body: <p>In Oracle, you can write:</p>
  
  <pre><code>update t
  set xml = updateXML(xml, '/a/b/text()', 'gaga')
  </code></pre>
  
  <p>This works only if you already have some text in the <code>&lt;b&gt;</code> element. How to update the document and "add some text" in <code>&lt;b&gt;</code> if the document in the database looks like:</p>
  
  <pre><code>&lt;a&gt;
      &lt;b/&gt;
  &lt;/a&gt;
  </code></pre>