TiDB + JavaScript (mysqljs/mysql)

Use this skill to connect to TiDB from Node.js with the mysql package (aka mysqljs/mysql), configure TLS correctly for TiDB Cloud, and provide small runnable snippets you can copy into a project.

Important: mysql vs mysql2

These two drivers are easy to mix up:

• This skill is for mysqljs/mysql (npm i mysql) which is primarily callback-based.
• If you want the promise-native driver mysql2 (npm i mysql2 / mysql2/promise), jump to the tidbx-javascript-mysql2 skill instead.

Recommendation: prefer an ORM for app code

For most application code (models, migrations, types), prefer an ORM/query builder:

• Prisma ORM: use tidbx-prisma
• Kysely query builder: use tidbx-kysely

When to use this skill

• Connect to TiDB from JavaScript/TypeScript (Node.js runtime) via mysql (mysqljs/mysql).
• Need TLS guidance (TiDB Cloud public endpoint) or CA certificate setup (TiDB Cloud Dedicated).
• Want a minimal "connect -> SELECT VERSION() -> CRUD" template using mysqljs/mysql.

Code generation rules (Node.js)

• Never hardcode credentials; use DATABASE_URL or TIDB_* env vars.
• Use parameterized queries with ? placeholders; never string-concatenate untrusted input.
• Prefer a pool for apps/services (createPool) and pool.end() on shutdown.
• mysqljs/mysql is callback-first; wrap callback APIs with util.promisify or small new Promise(...) helpers.

Install

npm i mysql

If you want .env support:

npm i dotenv

Minimal snippets

Option A: connect with DATABASE_URL (recommended)

import mysql from 'mysql'
import util from 'node:util'

const conn = mysql.createConnection(process.env.DATABASE_URL)
const query = util.promisify(conn.query).bind(conn)

const rows = await query('SELECT VERSION() AS v')
console.log(rows[0].v)
await util.promisify(conn.end).bind(conn)()

Option B: connect with connection options (TLS / CA)

Use this when you want explicit TLS config (common for TiDB Cloud Dedicated with a downloaded CA).

import mysql from 'mysql'
import fs from 'node:fs'

const conn = mysql.createConnection({
  host: process.env.TIDB_HOST,
  port: Number(process.env.TIDB_PORT ?? 4000),
  user: process.env.TIDB_USER,
  password: process.env.TIDB_PASSWORD,
  database: process.env.TIDB_DATABASE ?? 'test',
  ssl: process.env.TIDB_ENABLE_SSL === 'true'
    ? {
        minVersion: 'TLSv1.2',
        ca: process.env.TIDB_CA_PATH ? fs.readFileSync(process.env.TIDB_CA_PATH) : undefined,
      }
    : undefined,
})

Suggested env vars:

TIDB_HOST=...
TIDB_PORT=4000
TIDB_USER=...
TIDB_PASSWORD=...
TIDB_DATABASE=test
TIDB_ENABLE_SSL=true
# Optional (commonly used for TiDB Cloud Dedicated):
TIDB_CA_PATH=/absolute/path/to/ca.pem

Transactions (mysqljs/mysql)

import util from 'node:util'

const begin = util.promisify(conn.beginTransaction).bind(conn)
const commit = util.promisify(conn.commit).bind(conn)
const rollback = util.promisify(conn.rollback).bind(conn)
const query = util.promisify(conn.query).bind(conn)

try {
  await begin()
  await query('UPDATE players SET coins = coins + ? WHERE id = ?', [50, id])
  await commit()
} catch (e) {
  await rollback()
  throw e
}

Templates & scripts in this skill

• scripts/validate_connection.mjs -- reads DATABASE_URL or TIDB_*, connects, prints SELECT VERSION(), then exits.
• templates/quickstart.mjs -- minimal end-to-end: connect -> create table -> insert -> query -> update -> delete.