@Override
    String addValues() {
        String s;
        
        s = "VALUES(";
        for(int i = 0; i < valuesUsed.length; i++){
            if(i != valuesUsed.length-1)
                s += "'" + valuesUsed[i] + "', ";
            else if(m.getTfCustodian().getText().isEmpty())
                    s += "NULL)";
                else
                    s += "'" + valuesUsed[i] + "')";
        }
        
        return s;
    }