Node.js alternative to mysqli_fetch_array()?

Question

<?php
        $connect = mysqli_connect('localhost', "root", "", "test");
        if(!$connect){
            die(mysqli_connect_error());
        }

        $sql = "SELECT * FROM articles";
        $result = mysqli_query($connect, $sql) or die(mysqli_connect_error());
        while($row = mysqli_fetch_array($result)){ ?>
            <div class='article-div'>;
                <a href='articleviewer.php?id=$row[ID]' class='article-title'> . <?php $row['Title'] ?>. </a>;
            </div>;
        <?php }
        mysqli_close($connect);
    ?>

So I have this code in PHP, which is self-explanatory really. It fetches the MySQL in an array and keeps printing divs for each article while posting the article's title.How do I do this in node.js with express? I have the "mysql" module installed. So what's the node equivalent to the mysqli_fetch_array()?

Answer 1

As npm's mysql module documentation says, you simply need to make a query like:

connection.query('SELECT * FROM `books` WHERE `author` = "David"', function (error, results, fields) {
    // error will be an Error if one occurred during the query 
    // results will contain the results of the query 
    // fields will contain information about the returned results fields (if any) 
});

You can then iterate over results via simple loop. Note: In the beginning of the documentation, there is an explanation about how to connect to the database and configure it. Read that first :)

Answer 2

You can use mysql or node-mysql modules:

npm install -g mysql

or

npm install -g node-mysql

Below is example usage (assuming there is a table named example_table with columns ID , FileName and FileSize in database node_dev ):

var mysql = require('mysql'),
qid = '1'; // example ID

var db = mysql.createConnection({
  host     : 'localhost',
  user     : 'DATABASE_USER_HERE',
  password : 'DATABASE_PASSWORD_HERE',
  database : 'node_dev'
});

/* SQL */
db.connect();
db.query('SELECT * FROM `example_table` WHERE RowID=?', [qid], function(err, rows, fields) {
  if (err) {
    throw err;
    console.error(err);
  } else {
    for (var i = 0, len = rows.length; i < len; i++) {
      // either of those two will do:
      console.log(rows[i].FileName, rows[i].FileSize); 
      console.log(rows[i]['FileName'], rows[i]['FileSize']);
    }
  }
});
db.end();
/* SQL */

You'ill probably (most of the time) want to write simple middleware/microservices with other node modules such as express, http/https, Oauth2 which will monitor for requests, catch parameters and send some output parsed as JSON or something.