interview

home / developersection / interviews / what conflict resolution strategies would you use during online sync?

Ask Question
ICSM Computer

IT-Hardware & Networking

Ravi Vishwakarma is a dedicated Software Developer with a passion for crafting efficient and innovative solutions. With a keen eye for detail and years of experience, he excels in developing robust software systems that meet client needs. His expertise spans across multiple programming languages and technologies, making him a valuable asset in any software development project.

Follow
Can you answer this question?
Answer

1 Answers

ICSM Computer

ICSM Computer

10-Jul-2025

What conflict resolution strategies would you use during online sync (e.g., server-wins vs client-wins)?

When implementing conflict resolution strategies during online sync, you typically choose based on the nature of your application, the data importance, and user expectations. Here are the most common strategies, with pros/cons and when to use them:

1. Server-Wins (Last-Write-Wins by server)

  • Description: If there's a conflict, the server version overwrites the client's.
  • Use When:
    • The server holds the authoritative source of truth.
    • Changes on the client are usually not critical or are derived from server data.
  • Example: Stock market apps, CMS dashboards.
  • Pros:
    • Simple and centralized.
  • Cons:
    • Client-side edits may be lost silently.

2. Client-Wins

  • Description: The client version is pushed and overrides the server’s version.
  • Use When:
    • Offline-first apps where client changes are prioritized (e.g., personal notes, task apps).
  • Example: To-do apps like Google Keep.
  • Pros:
    • Feels responsive; user retains control.
  • Cons:
    • Can overwrite critical server data accidentally.

3. Last-Write-Wins (Timestamp-Based)

  • Description: Whichever update (client or server) is newest (based on timestamp) wins.
  • Use When:
    • You trust both sides and track update times.
  • Pros:
    • Automatic and simple.
  • Cons:
    • Prone to time drift issues if client clock is incorrect.

4. Manual Merge (User-Assisted)

  • Description: If conflict occurs, show both versions and let user choose or merge.
  • Use When:
    • Data is sensitive or collaborative.
  • Example: Document editing apps, CRM systems.
  • Pros:
    • No accidental data loss.
  • Cons:
    • Requires UI for conflict handling, and user effort.

5. Field-Level Merge

  • Description: Only update specific fields that changed; merge non-conflicting fields.
  • Use When:
    • Objects contain multiple independent fields (e.g., profile form: name, email, phone).
  • Pros:
    • Minimizes conflicts.
  • Cons:
    • More complex implementation.

6. Operational Transformation / CRDTs

  • Description: Merge changes at the operation level (like in collaborative editors).
  • Use When:
    • Real-time multi-user editing.
  • Example: Google Docs, collaborative whiteboards.
  • Pros:
    • Enables concurrent edits.
  • Cons:
    • Complex to build and maintain.

Recommended Hybrid Approach

In many real-world apps, a hybrid approach is best:

  • Use timestamp-based sync for simple objects.
  • Use field-level merges for form-based records.
  • Fall back to manual merge when high-value data is at risk.
  • Optionally allow configurable resolution policies (e.g., “Always prefer my device’s data”).
advertising
advertising

Liked By

We use cookies to ensure you have the best browsing experience on our website. By using our site, you acknowledge that you have read and understood our Cookie Policy & Privacy Policy