Selects with client-side nodejs+mysql

Question

I’m new to nodejs, I’ve always used php with mysql and I’m migrating to Node but I have some problems, make the Node connect in the database works perfectly however I get no success when trying to run straight by Chrome returns the error Net.createConnection is not a Function, as I am not so aware I don’t know if I need a framework to manage the application so that the browser understands the select’s without error, to require them to work I am using Browserify my code js

 var $ = require('jquery');
 var mysql = require('mysql');

 var con = mysql.createConnection({
 host:'localhost',
 port:'0000',
 user:'root',
 password:'123456',
 database:'qualquer'
 });

con.connect(function(err) {
if (err) throw err;
 con.query("select * From qualquer.teste", function (err, result, 
fields) {
if (err) throw err;
console.log(result);
});
connection.end();
});""

Answer 1

There is a big difference between PHP and Node. PHP gives the illusion that you can run Mysql commands on the client side because PHP can have a mix of HTML, Mysql and PHP in the same file that seems to be served to the browser. But this is an illusion. In fact all PHP and Mysql code runs on the server and for the browser goes another version of this code, processed, without PHP or Mysql. That is, the browser does not (and should never) have access to Mysql directly.

What you need to do is create routes/urls where the Node can run code and send back a response. On these routes that are called when you navigate to a page on the server, or when you send an ajax request, you can pass data to the server to know what to do. In PHP this data is made available in $_GET or $_POST, on Node this works differently, but you can also access this type of data.

Having said that, it is worth mentioning that on Node it is a good idea to use a library to create the server, otherwise you will have to do a lot of things by hand that is complex. Test for example the express.js. library An example using express.js would look like this:

Example of requested url: http://localhost:3000/user/2?lang=en

Example code on Node:

app.get('/user/:id', function(req, res) {
  const userId = Number(req.params.id);
  con.query("SELECT username From users WHERE id=" + userId, function(err, result) {
    if (err) {
      console.log(err);
      res.send('Something went wrong...');
    }
    const lang = req.query.lang;

    if (lang === 'en') res.send('The user name is ' + result.name);
    else res.send('O nome do utilizador é ' + result.name);
  });
});