# Sequelize

[![Build Status](https://travis-ci.org/sequelize/sequelize.svg?branch=v3)](https://travis-ci.org/sequelize/sequelize)
[![Windows Build status](https://ci.appveyor.com/api/projects/status/8xhttm9pxmbmtbwb/branch/v3?svg=true)](https://ci.appveyor.com/project/felixfbecker/sequelize/branch/master)
[![codecov](https://codecov.io/gh/sequelize/sequelize/branch/v3/graph/badge.svg)](https://codecov.io/gh/sequelize/sequelize)
[![Dependency Status](https://david-dm.org/sequelize/sequelize.svg)](https://david-dm.org/sequelize/sequelize)
[![Bountysource](https://www.bountysource.com/badge/team?team_id=955&style=bounties_received)](https://www.bountysource.com/teams/sequelize/issues?utm_source=Sequelize&utm_medium=shield&utm_campaign=bounties_received)
[![Slack Status](http://sequelize-slack.herokuapp.com/badge.svg)](http://sequelize-slack.herokuapp.com)

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

[Documentation](http://sequelize.readthedocs.org/en/latest/)

## Installation

`npm install sequelize`

From 3.0.0 and up Sequelize will follow SEMVER. 3.0.0 contains important security fixes so we highly recommend that users upgrade.

If you still use 1.7 please prefer to [Upgrading to 2.0](https://github.com/sequelize/sequelize/wiki/Upgrading-to-2.0) and the changelog between 2.0 and 3.0. 2.1 also has a breaking change.

## 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))

## Resources
- [Changelog](https://github.com/sequelize/sequelize/blob/master/changelog.md)
- [Getting Started](http://docs.sequelizejs.com/en/latest/docs/getting-started/)
- [Documentation](http://docs.sequelizejs.com/en/latest/)
- [API Reference](http://docs.sequelizejs.com/en/latest/)
- [Collaboration and pull requests](https://github.com/sequelize/sequelize/blob/master/CONTRIBUTING.md)
- [Roadmap](https://github.com/sequelize/sequelize/issues/2869)
- [Twitter](https://twitter.com/SequelizeJS): @SequelizeJS
- [IRC](http://webchat.freenode.net?channels=sequelizejs): sequelizejs on Freenode
- [Google Groups](https://groups.google.com/forum/#!forum/sequelize)
- [Add-ons & Plugins](https://github.com/sequelize/sequelize/wiki/Add-ons-&-Plugins)