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