Using Node and Mysql

I am working on angular app and php as backend that will do the data processing to MySQL. recently i found out node-mysql plugin for Nodejs that will communicate to MySQL through JS.

After the documentations provided there, i have a question which i want to ask here and need some enlightenment from all of you guys.

According to documentation, we will have to declare the connection in JS file as

var mysql      = require('mysql');
var connection = mysql.createConnection({
  host     : 'localhost',
  user     : 'me',
  password : 'secret',
  database : 'my_db'
});

connection.connect();

connection.query('SELECT 1 + 1 AS solution', function(err, rows, fields) {
  if (err) throw err;

  console.log('The solution is: ', rows[0].solution);
});

connection.end();

By providing all the sensitive database login data in JS, will it be a big hole for security issue there? if Yes, how can prevent it?

And the query will be done as well through the JS file

var mysql = require('mysql');
var pool  = mysql.createPool(...);

pool.getConnection(function(err, connection) {
  // Use the connection
  connection.query( 'SELECT something FROM sometable', function(err, rows) {
    // And done with the connection.
    connection.release();

    // Don't use the connection here, it has been returned to the pool.
  });
});

Is that mean that the attacker will easily to find out what is the query that we use to query to database? Unlike server side language like PHP where we just call the php file together with the params.

Is it safe to use this driver on Nodejs?

Sorry for being newbie with this such questions.