SQL> var my_xml clob
SQL> set autoprint on
SQL> declare
  2    l_ctx  dbms_xmlgen.ctxHandle;

  3    l_sql  varchar2(400);
  4  begin
  5    l_sql := 'select * from emp';
  6    l_ctx := dbms_xmlgen.newContext(l_sql);
  7    :my_xml := dbms_xmlgen.getXml(l_ctx);
  8  end;

  9  /

PL/SQL procedure successfully completed.

MY_XML
———————————————————————
<?xml version="1.0"?>

<ROWSET>
<ROW>
<EMPNO>7369</EMPNO>
<ENAME>SMITH</ENAME>
<JOB>CLERK</JOB>
...
</ROW>
</ROWSET>


SQL> set autoprint off