如何在PL / SQL中循环遍历XML

My XML looks like this :

我的XML看起来像这样：

<root>
  <row>
    <grade>A</grade>
    <Employee>
      <Name>ROBERT SUKIMIN</Name>
      <company>ABC</company>     
    </Employee>
    <Group>117761020</Group>
    <Designation>2014-03-21</Designation>
    <Company_code>5813044</Company_code>
  </row>
  <row>
    <grade>B</grade>
    <Employee>
      <Name>CECIL PAINEM</Name>
      <company>XYZ</company>
    </Employee>
    <Employee>
      <Name>SUGRIWO</Name>
      <company>BCA</company>
    </Employee>
    <Group>40560050</Group>
    <Designation>2012-05-03</Designation>
    <Company_code>0</Company_code>
  </row>
</root>
<root