private List<Fingerprint> getFingerprints(Integer fingerprintId, Integer locationId, Integer measurementId) { 
		String cnst = "";
		if (fingerprintId != -1) cnst += getTableName() + "." + getTableIdCol() + " = " + fingerprintId;
		else if (locationId != -1) cnst += getTableName() + "." + getTableCols()[0] + " = " + locationId;
		else if (measurementId != -1) cnst += getTableName() + "." + getTableCols()[1] + " = " + measurementId;
		return get(cnst);
	}