title: Can't trim the string in Oracle
body: <p>I have a string <code>IN-123456</code>; now I need to trim the <code>IN-</code> from that string. I tried as in Oracle</p>
  
  <pre><code>select trim('IN-' from 'IN-123456) from dual;
  </code></pre>
  
  <p>but I get an error</p>
  
  <pre><code>ORA-30001: trim set should have only one character
  30001. 00000 -  "trim set should have only one character"
  *Cause:    Trim set contains more or less than 1 character. This is not
             allowed in TRIM function.
  </code></pre>
  
  <p>How can I solve this?</p>