XML : SQL/xquery db2 xmltable

I have the following situation

  <customer>  <terminal>      <details>          <id>123</id>          <payment>              <type>type1</type>          </payment>      </details>  </terminal>  <terminal>      <details>          <id>123</id>          <payment>              <type>type1</type>          </payment>      </details>  </terminal>    

I am using xmltable. Is there a way to iterate over each terminal tag in a while loop. Also is there a way to know how many there are?

Thanks