docs: public boolean isComparable() throws SQLException {
  		if (fieldConfig.isForeignCollection()) {
  			return false;
  		}
  		/*
  		 * We've seen dataPersister being null here in some strange cases. Why? It may because someone is searching on
  		 * an improper field. Or maybe a table-config does not match the Java object?
  		 */
  		if (dataPersister == null) {
  			throw new SQLException("Internal error.  Data-persister is not configured for field.  "
  					+ "Please post _full_ exception with associated data objects to mailing list: " + this);
  		} else {
  			return dataPersister.isComparable();
  		}
  	}