express+mysql+vue项目入门-express服务端连接mysql数据库，此方法mysql为例：添加一个mysql连接模块并导出，在服务端入口导入使用即可

var mysql = require('mysql');

var connection = mysql.createConnection({
  host     : 'localhost',
  user     : 'root',
  password : 'root',
  port:3306,
  database:'mytest'
});
 
connection.connect(function(err) {
  if (err) {
  	console.log('mysql connection is exit error...')
    return false;
  }
  console.log('mysql connection already...')
});



module.exports = connection