Android SQLite and SQL Server Sync: CRUD Operations

Synchronizing data between Android's local SQLite databases and remote SQL Server databases is a common requirement for many applications. This article explores two ways to implement synchronization and perform CRUD (Create, Read, Update, Delete) operations effectively.

Technical Background

SQLite and SQL Server Overview

• SQLite: A lightweight, file-based database used predominantly in mobile applications due to its simplicity and ease of integration.
• SQL Server: A more robust and feature-rich database system used in enterprise environments. SQL Server is capable of handling a large amount of data and provides comprehensive performance features.

Synchronization between these databases ensures data consistency, availability, and reliability across different platforms.

Two Ways to Sync: Direct and Middleware Approach

1. Direct Synchronization

In direct synchronization, the Android device communicates directly with the SQL Server database. This method can be used in environments where secure direct access to the server is possible.

Example: RESTful API Synchronization

1. Create:
   • On the Android side, collect the data and store it temporarily in the SQLite database.
   • Use a RESTful API to send a POST request with JSON data to the SQL Server.
   • Perform a GET request to retrieve data from the server.
   • Update the SQLite database with the retrieved information.
   • Similar to Create , but utilize PUT methods to update records based on primary keys.
   • Use DELETE requests to remove records from the SQL Server, followed by updating SQLite.

• Pros: Direct control over synchronization, no intermediary services needed.
• Cons: Exposes server APIs directly, potential security issues, higher network overhead.
  • Data is sent to Firebase, which triggers Cloud Functions to update SQL Server accordingly.
  • Firebase provides real-time synchronization and offline capabilities.
  • Firebase triggers updates and deletions through similar Cloud Function logic.
• Pros: Enhanced security layer, real-time updates, scalability.
• Cons: Dependency on third-party services, potential additional costs.