title: Sort result from xmlagg(xmlelement(...)
body: <p>I got this SQL query: </p>
  
  <pre><code>        select rtrim(extract(xmlagg(xmlelement(e, column_name || ',')),
         '/E/text()').getclobval(), ',') from all_tab_columns
          where OWNER = 'TESTER' AND TABLE_NAME = 'H4_POSIT';
  </code></pre>
  
  <p>I using this instead of LISTAGG(column_name, ',') because the result is going to exceed the limit of varchar2 (>4000). 
  Now I am asking myself whether it is possible to sort the result like LISTAGG does it. </p>
  
  <p>So when having columns FERA, BAUT, CHECK_ID, ... I'd like them to be returned as: BAUT,CHECK_ID,FERA, ... </p>
  
  <p>I am using Oracle Server and my framework doesn't allow me to work with PL/SQL.</p>