title: Querying Oracle table with XPath/extract returning empty string
body: <p>I'm trying to extract values from XML that is similar to below and is stored in an Oracle 10g table:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;manifest xmlns="http://www.imsglobal.org/xsd/imscp_v1p1" ..."&gt;
      &lt;organizations&gt;
          &lt;organization identifier="***"&gt;&lt;item identifier="_745"&gt;&lt;item identifier="_9700"&gt;&lt;imsss:sequencing&gt;&lt;imsss:scoreAndRollup isCompletionRolledUp="false" isMasteryRolledUp="false" isScoreRequired="true" scoreRollupWeight="1.0"/&gt;&lt;/organization&gt;
      &lt;/organizations&gt;
      &lt;resources/&gt;
  &lt;/manifest&gt;
  </code></pre>
  
  <p>The query I'm trying to use is:</p>
  
  <pre><code>select xmltype(t.xml).extract('/manifest/organizations/organization').getStringVal() from BLAxml t
  </code></pre>
  
  <p>The data type of the xml column in the underlying table is CLOB.</p>
  
  <p>Unfortunately, every time I run this query it returns an empty string for the value rather than the contents of this portion of the XML statement.  It doesn't seem to matter what portion of the XML I'm pointing to, it gives me an empty string.  </p>
  
  <p>Any help would be greatly appreciated.  Thank you.</p>