title: result of string concatenation is too long after using to_clob
body: <p>I am trying to create a table view by running the sql below</p>
  
  <pre><code>  SELECT   IACM1.CMNT_REAS_TYP,
             TO_CLOB(LPAD (
                        LISTAGG (IACM1.CMNT_TXT, ' ')
                           WITHIN GROUP (ORDER BY IACM1.LN_NUM),
                        4000,
                        LISTAGG (IACM1.CMNT_TXT, ' ')
                           WITHIN GROUP (ORDER BY IACM1.LN_NUM)
                     ))
      FROM   FT_T_IACM IACM1, FT_T_IACM IACM2
     WHERE   IACM1.ISSACT_ID = IACM2.ISSACT_ID
             AND IACM1.CMNT_REAS_TYP = IACM2.CMNT_REAS_TYP
  GROUP BY   IACM1.cmnt_reas_typ;
  </code></pre>
  
  <p>But I am getting the <code>error</code> below </p>
  
  <blockquote>
    <p>ORA-01489: result of string concatenation is too long
    01489. 00000 -  "result of string concatenation is too long"
    *Cause:    String concatenation result is more than the maximum size.
    *Action:   Make sure that the result is less than the maximum size.</p>
  </blockquote>
  
  <p>I looked up and I found suggestions to use to_clob but it is still throwing this error. I am using oracle 11g. Thanks for the help in advance.</p>