https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/async_function

var mysql = require('promise-mysql');
var connection;

mysql.createConnection({
    host: 'localhost',
    user: 'sauron',
    password: 'theonetruering',
    database: 'mordor'
}).then(function(conn){
    connection = conn;
    return connection.query('select `id` from hobbits where `name`="frodo"');
}).then(function(rows){
    // Query the items for a ring that Frodo owns.
    var result = connection.query('select * from items where `owner`="' + rows[0].id + '" and `name`="ring"');
    connection.end();
    return result;
}).then(function(rows){
    // Logs out a ring that Frodo owns
    console.log(rows);
});

var mysql = require('promise-mysql');
var connection;

async function querySequentially(){
    connection = await mysql.createConnection({
        host: 'localhost',
        user: 'sauron',
        password: 'theonetruering',
        database: 'mordor'
    })
    var rows = await connection.query('select `id` from hobbits where `name`="frodo"');
    var result = await connection.query('select * from items where `owner`="' + rows[0].id + '" and `name`="ring"');
    console.log(result);
}