## Node MySQL 2

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[![NPM Version][npm-image]][npm-url]
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[![License][license-image]][license-url]

> MySQL client for Node.js with focus on performance. Supports prepared statements, non-utf8 encodings, binary log protocol, compression, ssl [much more](https://github.com/sidorares/node-mysql2/tree/master/documentation)

__Table of contents__

  - [History and Why MySQL2](#history-and-why-mysql2)
  - [Installation](#installation)
  - [First Query](#first-query)
  - [Using Prepared Statements](#using-prepared-statements)
  - [Using Promise Wrapper](#using-promise-wrapper)
  - [API and Configuration](#api-and-configuration)
  - [Documentation](#documentation)
  - [Acknowledgements](#acknowledgements)
  - [Contributing](#contributing)

## History and Why MySQL2

MySQL2 project is a continuation of [MySQL-Native][mysql-native]. Protocol parser code was rewritten from scratch and api changed to match popular [mysqljs/mysql][node-mysql]. MySQL2 team is working together with [mysqljs/mysql][node-mysql] team to factor out shared code and move it under [mysqljs][node-mysql] organisation.

MySQL2 is mostly API compatible with [mysqljs][node-mysql] and supports majority of features. MySQL2 also offers these additional features

 - Faster / Better Performance
 - [Prepared Statements](https://github.com/sidorares/node-mysql2/tree/master/documentation/Prepared-Statements.md)
 - MySQL Binary Log Protocol
 - [MySQL Server](https://github.com/sidorares/node-mysql2/tree/master/documentation/MySQL-Server.md)
 - Extended support for Encoding and Collation
 - [Promise Wrapper](https://github.com/sidorares/node-mysql2/tree/master/documentation/Promise-Wrapper.md)
 - Compression
 - SSL and [Authentication Switch](https://github.com/sidorares/node-mysql2/tree/master/documentation/Authentication-Switch.md)
 - [Custom Streams](https://github.com/sidorares/node-mysql2/tree/master/documentation/Extras.md)
 - Pooling

## Installation

MySQL2 is free from native bindings and can be installed on Linux, Mac OS or Windows without any issues.

```bash
npm install --save mysql2
```

## First Query

```js
// get the client
const mysql = require('mysql2');

// create the connection to database
const connection = mysql.createConnection({
  host: 'localhost',
  user: 'root',
  database: 'test'
});

// simple query
connection.query(
  'SELECT * FROM `table` WHERE `name` = "Page" AND `age` > 45',
  function(err, results, fields) {
    console.log(results); // results contains rows returned by server
    console.log(fields); // fields contains extra meta data about results, if available
  }
);

// with placeholder
connection.query(
  'SELECT * FROM `table` WHERE `name` = ? AND `age` > ?',
  ['Page', 45],
  function(err, results) {
    console.log(results);
  }
);
```

## Using Prepared Statements

With MySQL2 you also get the prepared statements. With prepared statements MySQL doesn't have to prepare plan for same query everytime, this results in better performance. If you don't know why they are important, please check these discussions

- [How prepared statements can protect from SQL Injection attacks](http://stackoverflow.com/questions/8263371/how-can-prepared-statements-protect-from-sql-injection-attacks)

MySQL provides `execute` helper which will prepare and query the statement. You can also manually prepare / unprepare statement with `prepare` / `unprepare` methods.

```js
// get the client
const mysql = require('mysql2');

// create the connection to database
const connection = mysql.createConnection({
  host: 'localhost',
  user: 'root',
  database: 'test'
});

// execute will internally call prepare and query
connection.execute(
  'SELECT * FROM `table` WHERE `name` = ? AND `age` > ?',
  ['Rick C-137', 53],
  function(err, results, fields) {
    console.log(results); // results contains rows returned by server
    console.log(fields); // fields contains extra meta data about results, if available

    // If you execute same statement again, it will be picked form a LRU cache
    // which will save query preparation time and give better performance
  }
);
```
## Using Promise Wrapper

MySQL2 also support Promise API. Which works very well with ES7 async await.

<!--eslint-disable-next-block-->
```js
async function main() {
  // get the client
  const  mysql = require('mysql2/promise');
  // create the connection
  const connection = await mysql.createConnection({host:'localhost', user: 'root', database: 'test'});
  // query database
  const [rows, fields] = await connection.execute('SELECT * FROM `table` WHERE `name` = ? AND `age` > ?', ['Morty', 14]);
}
```

MySQL2 use default `Promise` object available in scope. But you can choose which `Promise` implementation you want to use

<!--eslint-disable-next-block-->
```js
// get the client
const mysql = require('mysql2/promise');

// get the promise implementation, we will use bluebird
const bluebird = require('bluebird');

// create the connection, specify bluebird as Promise
const connection =  mysql.createConnection({host:'localhost', user: 'root', database: 'test', Promise: bluebird});

// query database
const [rows, fields] =  connection.execute('SELECT * FROM `table` WHERE `name` = ? AND `age` > ?', ['Morty', 14]);
```

## API and Configuration

MySQL2 is mostly API compatible with [Node MySQL][node-mysql]. You should check their API documentation to see all available API options.

If you find any incompatibility with [Node MySQL][node-mysql], Please report via Issue tracker. We will fix reported incompatibility on priority basis.

## Documentation

You can find more detailed documentation [here](https://github.com/sidorares/node-mysql2/tree/master/documentation). You should also check various code [examples](https://github.com/sidorares/node-mysql2/tree/master/examples) to understand advanced concepts.

## Acknowledgements

  - Internal protocol is written by @sidorares [MySQL-Native](https://github.com/sidorares/nodejs-mysql-native)
  - Constants, SQL parameters interpolation, Pooling, `ConnectionConfig` class taken from [node-mysql](https://github.com/mysqljs/mysql)
  - SSL upgrade code based on @TooTallNate [code](https://gist.github.com/TooTallNate/848444)
  - Secure connection / compressed connection api flags compatible to [MariaSQL](https://github.com/mscdex/node-mariasql/) client.
  - [Contributors](https://github.com/sidorares/node-mysql2/graphs/contributors)

## Contributing

Want to improve something in `node-mysql2`. Please check [Contributing.md](https://github.com/sidorares/node-mysql2/blob/master/Contributing.md) for detailed instruction on how to get started.


[npm-image]: https://img.shields.io/npm/v/mysql2.svg
[npm-url]: https://npmjs.org/package/mysql2
[node-version-image]: http://img.shields.io/node/v/mysql2.svg
[node-version-url]: http://nodejs.org/download/
[travis-image]: https://img.shields.io/travis/sidorares/node-mysql2/master.svg?label=linux
[travis-url]: https://travis-ci.org/sidorares/node-mysql2
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[appveyor-url]: https://ci.appveyor.com/project/sidorares/node-mysql2
[downloads-image]: https://img.shields.io/npm/dm/mysql2.svg
[downloads-url]: https://npmjs.org/package/mysql2
[license-url]: https://github.com/sidorares/node-mysql2/blob/master/License
[license-image]: https://img.shields.io/npm/l/mysql2.svg?maxAge=2592000
[node-mysql]: https://github.com/mysqljs/mysql
[mysql-native]: https://github.com/sidorares/nodejs-mysql-native
