How to fix CR_VERSION_ERROR (2007): Protocol mismatch in MySQL

// CORRECT: Using port 3306 (classic protocol)
const connection = mysql.createConnection({
  host: 'localhost',
  user: 'root',
  password: 'password',
  database: 'mydb',
  port: 3306
});

// WRONG: Using port 33060 with classic MySQL client
const connection = mysql.createConnection({
  host: 'localhost',
  user: 'root',
  password: 'password',
  database: 'mydb',
  port: 33060  // This is X Protocol port, incompatible with mysql/mysql2
});

# On MySQL server
mysql --version
SELECT VERSION();

# Check Node.js mysql2 version
npm list mysql2

# Update mysql2 package
npm install mysql2@latest

# Update mysql package (older, less recommended)
npm install mysql@latest

# CORRECT: Maps container port 3306 to host port 3306
docker run -d -p 3306:3306 mysql:8.0

# WRONG: Maps container port 33060 to host port 3306
docker run -d -p 3306:33060 mysql:8.0

# docker-compose.yml - CORRECT
services:
  db:
    image: mysql:8.0
    ports:
      - "3306:3306"  # host:container
    environment:
      MYSQL_ROOT_PASSWORD: password

# Application connection
host: db
port: 3306

# Start MySQL server with legacy authentication
mysql --default-authentication-plugin=mysql_native_password

# Or in my.cnf
[mysqld]
default-authentication-plugin=mysql_native_password

docker run -d -p 3306:3306 mysql:8.0 --default-authentication-plugin=mysql_native_password

const mysql = require('mysql2/promise');

const connection = await mysql.createConnection({
  host: 'localhost',
  user: 'root',
  password: 'password',
  database: 'mydb',
  port: 3306  // Classic MySQL port
});

console.log('Connected successfully!');
await connection.end();