# Sequelize

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Sequelize is a promise-based Node.js ORM for Postgres, MySQL, SQLite and Microsoft SQL Server. It features solid transaction support, relations, read replication and more.

## Table of Contents
- [Installation](#installation)
- [Features](#features)
- [Documentation](#documentation)
- [Responsible disclosure](#responsible_disclosure)
- [Resources](#resources)

## Installation

```bash
$ npm install --save sequelize

# And one of the following:
$ npm install --save pg pg-hstore
$ npm install --save mysql2
$ npm install --save sqlite3
$ npm install --save tedious // MSSQL
```

Sequelize follows [SEMVER](http://semver.org). Supports Node v4 and above to use ES6 features.

## Features

- Schema definition
- Schema synchronization/dropping
- 1:1, 1:M & N:M Associations
- Through models
- Promises
- Hooks/callbacks/lifecycle events
- Prefetching/association including
- Transactions
- Migrations
- CLI ([sequelize-cli](https://github.com/sequelize/cli))

## Documentation

- [Stable v4 documentation](http://docs.sequelizejs.com)
- [Upgrading from v3 to v4](http://docs.sequelizejs.com/manual/tutorial/upgrade-to-v4.html)
- [v3 documentation](https://sequelize.readthedocs.io/en/v3/)

## Responsible disclosure
If you have any security issue to report, contact project maintainers privately. You can find contact information [here](https://github.com/sequelize/sequelize/blob/master/CONTACT.md)

## Resources
- [Changelog](https://github.com/sequelize/sequelize/releases)
- [Getting Started](http://docs.sequelizejs.com/manual/installation/getting-started)
- [Contributing](https://github.com/sequelize/sequelize/blob/master/CONTRIBUTING.md)
- [Express Example](https://github.com/sequelize/express-example)
- [Documentation](http://docs.sequelizejs.com)
- [Slack](http://sequelize-slack.herokuapp.com/)
- [Google Groups](https://groups.google.com/forum/#!forum/sequelize)
- [Add-ons & Plugins](https://github.com/sequelize/sequelize/wiki/Add-ons-&-Plugins)