A terminal-based visualization tool for testing SQL transaction sequences.

• Why ACID?
• Demo
• Features
• Quick Start
• Controls
• Contributing
• License

Testing complex transaction scenarios usually requires:

• Opening multiple terminal windows
• Manually copying and pasting SQL commands in precise order
• Coordinating timing between different sessions
• Managing database connections and states

ACID eliminates this complexity by letting you define entire scenarios in simple Go code and watch them run automatically with visual feedback.

Instead of juggling terminals, you get:

• Automated execution - No manual copy-paste between terminals
• Real-time visualization - Watch scenarios execute with live updates
• Visual locks indicator - See exactly when transactions are waiting
• Quiz mode - Hide results to test your understanding

Perfect for learning transaction behavior, debugging concurrency issues, and teaching database concepts.

Get answers to your questions:

• Do I lose data when another request happens at the same time?
• What results do I get from a SELECT while another transaction is updating?
• What happens with SELECT COUNT(*) FROM table FOR UPDATE?

☝️ click to open app demo video

👇 [Ru lang] Click to watch ACID in action - BigTech SQL essentials video

// Test isolation levels with concurrent transactions
call.Setup("DROP TABLE IF EXISTS users"),
call.Setup("CREATE TABLE users (id SERIAL PRIMARY KEY, name TEXT, balance INTEGER)"),
call.Setup("INSERT INTO users (name, balance) VALUES ('Alice', 1000), ('Bob', 500)"),

call.Begin(tx1), // Transaction 1: Transfer money  
call.Begin(tx2), // Transaction 2: Check balances

call.Call("UPDATE users SET balance = balance - 100 WHERE name = 'Alice'", tx1),
call.Call("SELECT balance FROM users WHERE name = 'Alice'", tx2), // What balance is shown?
call.Commit(tx1),
call.Call("SELECT balance FROM users WHERE name = 'Alice'", tx2), // What about now?
call.Commit(tx2),

Easily create runnable sequences:

• Setup for initialization SQL (hidden by default)
  • Press the s button to see initialization code call result
• Begin, Commit, Rollback parallel transactions
  • Argument: txID to start or finish
• Call SQL request
  • Second argument: txID to run SQL inside. If no txID is provided, runs as a single query transaction (begin → SQL call → commit)

SQL sequences run with hidden responses, allowing you to test your understanding or quiz others on transaction behavior.

Press m or space to show responses.

Every request runs concurrently, with the UI showing when transactions wait for resource access.

Explore predefined sequences for common transaction scenarios.

⚠️ Requirements

This tool requires a running PostgreSQL or MySQL database

• Go 1.23+ to run program
• Docker and Docker Compose (for local databases run command)
• OR access to PostgreSQL/MySQL database

git clone https://github.com/rusinikita/acid.git

Run PostgreSQL and MySQL in Docker

make rundbs

Or

docker compose up -d

Alternatively, you can create a cloud database in 3 minutes:

• neon.com for postgres
• planetscale.com for mysql

Create .env file from .env.example content

cp .env.example .env

By default .env.example file is ready to connect to Postgresql in docker

You can edit the .env content:

• If you want to test MySQL-specific cases in Docker Compose - simply uncomment the MySQL section and comment out the PostgreSQL section
• Or edit environment variables for another database link

# postgresql
# DB_DRIVER=postgres
# DB_CONNECT="host=localhost port=5432 user=acid password=strong_password_123 dbname=demo sslmode=disable"
# mysql
DB_DRIVER=mysql
DB_CONNECT="acid:strong_password_123@tcp(127.0.0.1:3306)/demo"

make run

Or

go run main.go

Use arrow keys to select a sequence and press Enter to run it.

Edit queries or create your own sequences in sequence/sequences.go file.

• PostgreSQL
• MySQL

We welcome contributions! Here's how you can help:

1. Report Issues - Found a bug or have a feature request? Create an issue
2. Share Sequences - Create interesting transaction scenarios in sequence/sequences.go
3. Improve Documentation - Help make the README clearer
4. Code Contributions - Submit pull requests for bug fixes or features

GPL-3.0 License - see LICENSE file for details.