Examples

Simple SELECT

Promise

import mysql from 'mysql2/promise';

const connection = await mysql.createConnection({
  user: 'test',
  database: 'test',
});

const [rows] = await connection.query('SELECT 1+1 AS `test1`');
// ...

Callback

const mysql = require('mysql2');

const connection = mysql.createConnection({
  user: 'test',
  database: 'test',
});

connection.query('SELECT 1+1 AS `test1`', (err, rows) => {
  // ...
});

---

Prepared Statement and Parameters

Promise

import mysql from 'mysql2/promise';

const connection = await mysql.createConnection({
  user: 'test',
  database: 'test',
});

const [rows] = await connection.execute('SELECT 1+? AS `test1`', [10]);
// ...

Callback

const mysql = require('mysql2');

const connection = mysql.createConnection({
  user: 'test',
  database: 'test',
});

connection.execute('SELECT 1+? as test1', [10], (err, rows) => {
  // ...
});

---

Connecting over encrypted connection

Promise

import fs from 'fs';
import mysql from 'mysql2/promise';

const connection = await mysql.createConnection({
  user: 'test',
  database: 'test',
  ssl: {
    key: fs.readFileSync('./certs/client-key.pem'),
    cert: fs.readFileSync('./certs/client-cert.pem'),
  },
});

console.log(await connection.query('SELECT 1+1 AS `test1`'));

Callback

const fs = require('fs');
const mysql = require('mysql2');

const connection = mysql.createConnection({
  user: 'test',
  database: 'test',
  ssl: {
    key: fs.readFileSync('./certs/client-key.pem'),
    cert: fs.readFileSync('./certs/client-cert.pem'),
  },
});

connection.query('SELECT 1+1 AS `test1`', console.log);

You can use 'Amazon RDS' string as value to ssl property to connect to Amazon RDS mysql over ssl (in that case https://s3.amazonaws.com/rds-downloads/mysql-ssl-ca-cert.pem CA cert is used)

Promise

import mysql from 'mysql2/promise';

try {
  const connection = await mysql.createConnection({
    user: 'foo',
    password: 'bar',
    host: 'db.id.ap-southeast-2.rds.amazonaws.com',
    ssl: 'Amazon RDS',
  });

  const [res] = await connection.query("SHOW `status` LIKE 'Ssl_cipher'");

  console.log(res);
  connection.end();
} catch (err) {
  console.log(err);
}

Callback

const mysql = require('mysql2');

const connection = mysql.createConnection({
  user: 'foo',
  password: 'bar',
  host: 'db.id.ap-southeast-2.rds.amazonaws.com',
  ssl: 'Amazon RDS',
});

connection.query("SHOW `status` LIKE 'Ssl_cipher'", (err, res) => {
  console.log(err, res);
  connection.end();
});

---

Simple MySQL proxy server

const mysql = require('mysql2');

const server = mysql.createServer();
server.listen(3307);
server.on('connection', (conn) => {
  console.log('connection');

  conn.serverHandshake({
    protocolVersion: 10,
    serverVersion: 'node.js rocks',
    connectionId: 1234,
    statusFlags: 2,
    characterSet: 8,
    capabilityFlags: 0xffffff,
  });

  conn.on('field_list', (table, fields) => {
    console.log('field list:', table, fields);
    conn.writeEof();
  });

  const remote = mysql.createConnection({
    user: 'root',
    database: 'dbname',
    host: 'server.example.com',
    password: 'secret',
  });

  conn.on('query', (sql) => {
    console.log(`proxying query: ${sql}`);
    remote.query(sql, function (err) {
      // overloaded args, either (err, result :object)
      // or (err, rows :array, columns :array)
      if (Array.isArray(arguments[1])) {
        // response to a 'select', 'show' or similar
        const rows = arguments[1],
          columns = arguments[2];
        console.log('rows', rows);
        console.log('columns', columns);
        conn.writeTextResult(rows, columns);
      } else {
        // response to an 'insert', 'update' or 'delete'
        const result = arguments[1];
        console.log('result', result);
        conn.writeOk(result);
      }
    });
  });

  conn.on('end', remote.end.bind(remote));
});

---

Examples using MySQL server API

• MySQL-pg-proxy - MySQL to Postgres proxy server.
• MySQLite.js - MySQL server with JS-only (emscripten compiled) sqlite backend.
• SQL-engine - MySQL server with LevelDB backend.
• MySQL-osquery-proxy - Connect to facebook osquery using MySQL client
• PlyQL - Connect to Druid using MySQL client