public int compareTo(DBType t) {
		StringType st = null;
		if (t instanceof StringType) {
			st = (StringType) t; 
		} else {
			return -1;
		}
		String i = st.get();
		
		if (i == null && value == null) {
			return 0;
		} else if (i != null && value == null) {
			return -1;
		} else if (i == null && value != null) {
			return 1;
		}
		
		int myLen = value.length();
		int len = i.length();
		if (myLen > len) {
			String s = value.substring(0, len);
			return s.compareTo(i);
		} else if (myLen < len) {
			return value.compareTo(i.substring(0, myLen));
		} 
		return value.compareTo(i);
	}