node-red-nodes/storage/mysql/README.md

node-red-node-mysql
========================
A <a href="http://nodered.org" target="_new">Node-RED</a> node to read and write to a MySQL database.

Install
-------

Either use the `Node-RED Menu - Manage Palette - Install`, or run the following command in your Node-RED user directory - typically `~/.node-red`

    npm i node-red-node-mysql


Usage
-----

Allows basic access to a MySQL database.

This node uses the <b>query</b> operation against the configured database. This does allow both INSERTS and DELETES.

By its very nature it allows SQL injection... so <i>be careful out there...</i>

The `msg.topic` must hold the <i>query</i> for the database, and the result is returned in `msg.payload`.

Typically the returned payload will be an array of the result rows.

If nothing is found for the key then <i>null</i> is returned.

The reconnect retry timeout in milliseconds can be changed by adding a line to <b>settings.js</b>
    <pre>mysqlReconnectTime: 30000,</pre></p>


Preparing Queries
-----
```javascript
msg.payload=[24, 'example-user'];
msg.topic="INSERT INTO users (`userid`, `username`) VALUES (?, ?);"
return msg;
```

with named parameters:

```javascript
msg.payload={}
msg.payload.userToChange=42;
msg.payload.newUsername="example-user";
msg.topic="INSERT INTO users (`userid`, `username`) VALUES (:userToChange, :newUsername) ON DUPLICATE KEY UPDATE `username`=:newUsername;"
return msg;
```
Documentation
-----
    
<a href="https://www.npmjs.com/package/mysql" target="_new">Documentation</a> of the used Node.js package