mysql-emulator

library0.1.0jsnpmunverified

MySQL emulator that runs entirely in Node.js without a real MySQL server, designed for end-to-end testing. Current version 0.1.0 is in active development with known limitations (no RIGHT JOIN, no timezone support, partial INFORMATION_SCHEMA). It integrates with Sequelize 6+ and TypeORM 0.3+ via peer dependencies, supporting common SQL operations including SELECT, INSERT, UPDATE, DELETE, foreign key constraints, and basic functions. Unlike MySQL mock libraries that only intercept queries, this emulator parses and executes SQL internally, providing more realistic behavior for e2e tests.

testing database

npm install mysql-emulator

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · MYSQL-EMULATOR

mysql-emulator

testingjavascriptv0.1.0

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

query

✓ import { query } from 'mysql-emulator'

✗ const mysql = require('mysql-emulator');

ESM-only; no CommonJS support.

createConnection

✓ import { createConnection } from 'mysql-emulator'

✗ import createConnection from 'mysql-emulator'

Named export, not default.

getConnectionManager

✓ import { getConnectionManager } from 'mysql-emulator'

TypeScript types included; use for managing multiple connections.

Creates a MySQL emulator connection, creates a table, inserts a row, and queries it, demonstrating basic SQL execution.

import { query, createConnection } from 'mysql-emulator'; async function main() { const conn = createConnection(); await conn.query('CREATE TABLE IF NOT EXISTS users (id INT AUTO_INCREMENT PRIMARY KEY, name VARCHAR(255))'); await conn.query('INSERT INTO users (name) VALUES (?)', ['Alice']); const results = await query('SELECT * FROM users'); console.log(results); } main().catch(console.error);

Debug

Known issues

breakingRIGHT JOIN is not supported

fix

Rewrite queries using LEFT JOIN or other workarounds.

affects: <=0.1.0

deprecatedNo INFORMATION_SCHEMA tables are filled

fix

Avoid relying on INFORMATION_SCHEMA for introspection; use explicit schema queries.

affects: <=0.1.0

gotchaDefault ORDER may differ from real MySQL; always use ORDER BY when order matters

fix

Add explicit ORDER BY to your queries.

affects: all

gotchaColumn names may differ from real MySQL, e.g., `count(u.id)` becomes `COUNT(``u``.``id``)`

fix

Use column aliases to normalize names.

affects: all

gotchaNo timezone support; all date/time operations assume UTC

fix

Manually convert timezones in application logic.

affects: all

Errors

Common errors & fixes

Error: Cannot find module 'mysql-emulator'

Package not installed or not in node_modules

fix

Run npm install mysql-emulator

TypeError: mysql.createConnection is not a function

Using CommonJS require with an ESM-only package

fix

Use import syntax instead of require()

Error: RIGHT JOIN not implemented

Query uses RIGHT JOIN which is unsupported

fix

Rewrite query with LEFT JOIN

Error: Unknown column 'X' in 'field list'

Column name mismatch due to backtick handling

fix

Use consistent quoting or aliases

Upgrade

Version history

0.1.0latest on npm

Audit

Dependencies

sequelizeoptionalPeer dependency for Sequelize integration; requires sequelize@>=6.0.0

typeormoptionalPeer dependency for TypeORM integration; requires typeorm@>=0.3.0

Agent activity

18 hits · last 30 days

node

Resources

githubhttps://github.com/i-van/mysql-emulator ↗

packagemysql-emulator ↗

homepagehttps://github.com/i-van/mysql-emulator#readme ↗