Design Version Control Github - Database Modelling Part 1

Features Included

1. User Authentication: Secure login and registration.

2. Repository Management: Creating, updating, and deleting repositories.

3. Branching and Merging: Support for branching, merging, and resolving conflicts.

4. File Management: Uploading, updating, and deleting files within repositories.

5. Commit Tracking: Recording and managing commits made by users.

6. Pull Requests: Users can submit pull requests to propose changes to repositories.

7. Issue Tracking: Users can create, assign, and close issues related to repositories.

8. Collaboration: Support for multiple users collaborating on the same repository.

9. Code Review: Reviewing and commenting on code changes.

10. Notifications: Email or in-app notifications for repository activities.

Entity/Table with Detailed Info about Every Value with Code

1. Users Table:

    CREATE TABLE Users (
        user_id INT AUTO_INCREMENT PRIMARY KEY,
        username VARCHAR(255) NOT NULL,
        email VARCHAR(255) NOT NULL UNIQUE,
        password_hash VARCHAR(255) NOT NULL,
        created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
    );
   

2. Repositories Table:

    CREATE TABLE Repositories (
        repo_id INT AUTO_INCREMENT PRIMARY KEY,
        user_id INT NOT NULL,
        name VARCHAR(255) NOT NULL,
        description TEXT,
        created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
        FOREIGN KEY (user_id) REFERENCES Users(user_id)
    );
   

3. Commits Table:

    CREATE TABLE Commits (
        commit_id INT AUTO_INCREMENT PRIMARY KEY,
        repo_id INT NOT NULL,
        user_id INT NOT NULL,
        message TEXT,
        timestamp TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
        FOREIGN KEY (repo_id) REFERENCES Repositories(repo_id),
        FOREIGN KEY (user_id) REFERENCES Users(user_id)
    );
   

4. Files Table:

    CREATE TABLE Files (
        file_id INT AUTO_INCREMENT PRIMARY KEY,
        repo_id INT NOT NULL,
        filename VARCHAR(255) NOT NULL,
        content TEXT,
        commit_id INT NOT NULL,
        timestamp TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
        FOREIGN KEY (repo_id) REFERENCES Repositories(repo_id),
        FOREIGN KEY (commit_id) REFERENCES Commits(commit_id)
    );
   

5. Issues Table:

    CREATE TABLE Issues (
        issue_id INT AUTO_INCREMENT PRIMARY KEY,
        repo_id INT NOT NULL,
        title VARCHAR(255) NOT NULL,
        description TEXT,
        status VARCHAR(50) DEFAULT 'open',
        created_by INT NOT NULL,
        assigned_to INT,
        created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
        FOREIGN KEY (repo_id) REFERENCES Repositories(repo_id),
        FOREIGN KEY (created_by) REFERENCES Users(user_id),
        FOREIGN KEY (assigned_to) REFERENCES Users(user_id)
    );
   

6. Pull Requests Table:

    CREATE TABLE PullRequests (
        pr_id INT AUTO_INCREMENT PRIMARY KEY,
        repo_id INT NOT NULL,
        title VARCHAR(255) NOT NULL,
        description TEXT,
        status VARCHAR(50) DEFAULT 'open',
        created_by INT NOT NULL,
        assigned_to INT,
        created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
        FOREIGN KEY (repo_id) REFERENCES Repositories(repo_id),
        FOREIGN KEY (created_by) REFERENCES Users(user_id),
        FOREIGN KEY (assigned_to) REFERENCES Users(user_id)
    );
   

ER Diagram Using Mermaid Chart

Details about 1-NF, 2-NF, etc., of Each Table in Tabular Format with Explanation Details

All Queries Required for Applications with Code

1. Retrieve Commits for a Repository:

    SELECT * FROM Commits
    WHERE repo_id = :repo_id;
   

2. Retrieve Files in a Repository:

    SELECT * FROM Files
    WHERE repo_id = :repo_id;
   

3. Retrieve Issues for a Repository:

    SELECT * FROM Issues
    WHERE repo_id = :repo_id;
   

4. Retrieve Pull Requests for a Repository:

    SELECT * FROM PullRequests
    WHERE repo_id = :repo_id;
   

5. Retrieve Users who Made Commits:

    SELECT u.username, c.message
    FROM Users u
    JOIN Commits c ON u.user_id = c.user_id;
   

All Required Indexing or Background Jobs with SQL Code

1. Indexing:

   • Index on user_id in the Users table for fast user lookup:

       CREATE INDEX idx_user_id ON Users (user_id);
     

   • Index on repo_id in the Repositories table for efficient repository retrieval:

       CREATE INDEX idx_repo_id ON Repositories (repo_id);
     

   • Index on repo_id in the Commits table for optimizing commit queries:

       CREATE INDEX idx_repo_id ON Commits (repo_id);
     

   • Index on repo_id in the Files table for efficient file retrieval:

       CREATE INDEX idx_repo_id ON Files (repo_id);
     

   • Index on repo_id in the Issues table for fast issue retrieval:

       CREATE INDEX idx_repo_id ON Issues (repo_id);
     

   • Index on repo_id in the PullRequests table for efficient pull request retrieval:

       CREATE INDEX idx_repo_id ON PullRequests (repo_id);
     

2. Background Jobs:

   • Regularly update statistics and analytics related to repository activities.

   • Periodically clean up old or unused data to optimize storage usage.

   • Background tasks to process asynchronous events such as webhook notifications.

Query Plan Optimization with Code

1. Query Optimization:

   • Analyze query execution plans using database-specific tools (e.g., EXPLAIN in MySQL) to identify bottlenecks.

   • Use appropriate indexes on frequently queried columns to improve query performance.

   • Rewrite complex queries to simplify execution and reduce resource usage.

   • Monitor and adjust database configuration parameters to optimize memory usage, disk I/O, and CPU utilization.

2. Caching:

   • Implement caching mechanisms at the application level to cache frequently accessed data and reduce database load.

   • Use caching solutions such as Redis or Memcached to store and retrieve cached data efficiently.

3. Partitioning:

   • Consider partitioning large tables based on criteria such as date ranges or repository size to distribute data across multiple storage devices and improve query performance.

4. Load Balancing:

   • Distribute read and write operations across multiple database replicas or shards to distribute the workload and improve scalability.

By implementing these query optimizations, indexing strategies, background jobs, and query plan optimizations, the Version Control System can handle large-scale repository management efficiently, ensuring optimal performance for users interacting with the system.

Will Discuss more about other features like branching and etc. in next post.