code: public SubString substring(int start) {
  		JcNumber sub = new JcNumber(start, this, OPERATOR.Common.COMMA_SEPARATOR);
  		SubString ret = new SubString(null, sub,
  				new FunctionInstance(FUNCTION.String.SUBSTRING, 2));
  		QueryRecorder.recordInvocationConditional(this, "substring", ret, QueryRecorder.literal(start));
  		return ret;
  	}
docs: <div color='red' style="font-size:24px;color:red"><b><i><u>JCYPHER</u></i></b></div>
  <div color='red' style="font-size:18px;color:red"><i>specify the start offset of a substring to be extracted</i></div>
  <br/>