app.js

/*
    SETUP
*/

// Express
var express = require('express');
var app = express();
PORT = 9124;

// Database
var db = require('./database/db-connector')

/*
    ROUTES
*/
app.get('/', function(req, res)
    {
        // Define our queries
        query1 = 'DROP TABLE IF EXISTS diagnostic;';
        query2 = 'CREATE TABLE diagnostic(id INT PRIMARY KEY AUTO_INCREMENT, text VARCHAR(255) NOT NULL);';
        query3 = 'INSERT INTO diagnostic (text) VALUES ("MySQL is working for myONID!")'; // replace with your ONID
        query4 = 'SELECT * FROM diagnostic;';

        // Execute every query in an asynchronous manner, we want each query to finish before the next one starts

        // DROP TABLE...
        db.pool.query(query1, function (err, results, fields){

            // CREATE TABLE...
            db.pool.query(query2, function(err, results, fields){

                // INSERT INTO...
                db.pool.query(query3, function(err, results, fields){

                    // SELECT *...
                    db.pool.query(query4, function(err, results, fields){

                        // Send the results to the browser
                        let base = "<h1>MySQL Results:</h1>"
                        res.send(base + JSON.stringify(results));
                    });
                });
            });
        });
    });

/*
    LISTENER
*/
app.listen(PORT, function(){
    console.log('Express started on http://localhost:' + PORT + '; press Ctrl-C to terminate.')
});