Linking Students with Courses and Grades in Firebase using Java

Courses
1

My Firebase project has teachers and students. I need help linking students to courses so teachers can assign grades. See my revised code snippet below.

public class CourseListAdapter extends FirebaseRecyclerAdapter<Course, CourseListAdapter.CourseHolder> {

    public CourseListAdapter(FirebaseRecyclerOptions<Course> opts) {
        super(opts);
    }

    @Override
    protected void onBindViewHolder(@NonNull CourseHolder holder, int pos, @NonNull Course info) {
        holder.courseTitle.setText(info.getTitle());
        holder.courseDetail.setText(info.getSummary());
    }

    @NonNull
    @Override
    public CourseHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.course_item_layout, parent, false);
        return new CourseHolder(view);
    }

    public static class CourseHolder extends RecyclerView.ViewHolder {
        TextView courseTitle, courseDetail;
        Button enrollBtn;

        public CourseHolder(@NonNull View itemView) {
            super(itemView);
            courseTitle = itemView.findViewById(R.id.courseTitleText);
            courseDetail = itemView.findViewById(R.id.courseDetailText);
            enrollBtn = itemView.findViewById(R.id.enrollButton);
            enrollBtn.setOnClickListener(v -> {
                FirebaseAuth auth = FirebaseAuth.getInstance();
                String userId = auth.getCurrentUser().getUid();
                FirebaseDatabase.getInstance().getReference("school/students/" + userId);
            });
        }
    }
}
2

In my experience linking students to courses in Firebase, it is beneficial to perform a multi-path update whenever a student enrolls. This way you can write to two parts of your database simultaneously, ensuring that the enrollment and course information are both updated. Personally, I followed an approach where after clicking the enroll button, I update the student’s record with the relevant course ID and also reflect this change on the course node. This has minimized data inconsistencies and provided a more reliable way to assign grades and track enrollments.

3

Hey all, I’ve been noodling around with similar ideas recently and was wondering if anyone has explored the use of transactions in Firebase for these kinds of multi-step updates. I’ve found that when you try to sync enrollment info between a student’s record and the course node at the same time, sometimes you run into race conditions if two operations hit almost simultaneously. One idea that popped into my head is whether leveraging Firebase Cloud Functions could ensure the consistency of these linked updates, offloading some logic from the client side. Has anyone experimented with that approach? Also, I’m curious about your experiences with handling rollbacks if something goes wrong. How do you guys ensure users aren’t left with partial updates? :blush: Would love to hear your thoughts or any clever patterns you’ve discovered!

4

hey, try addin an extra call in the enroll button to update the students courses list so grades can be later assigned. might be simplest thru a join-to entry in firebase. good luck!