public ArrayList<String[]> gridData() throws SQLException {
        completeLst = new ArrayList<>();
        String str = new String();
        String query = ("SELECT GRID FROM save;");
        preStmt = cnx.prepareStatement(query);
        result = preStmt.executeQuery();
        while (result.next()) {
            str = result.getString("GRID");
        }
        preStmt.close();
        String[] tab1 = str.split(";");
        for (int i = 0; i < tab1.length; i++) {
            String[] tab2 = tab1[i].split(",");
            completeLst.add(tab2);
        }
        return completeLst;
    }