Node.js - MySQL Select query

In this article, we would like to show you how to make SQL SELECT query in Node.js.

Note: at the end of this article you can find database preparation SQL queries.

1. SELECT query examples

const mysql = require('mysql');

const connection = mysql.createConnection({                 // gets connection with database
    host: 'localhost',  // '127.0.0.1'
    user: 'root',
    password: 'password',
    database: 'my_database',
});

connection.connect((error) => {
    if (error) throw error;
    const query = 'SELECT * FROM ??';
    const tableName = ['users'];       // SELECT * FROM `users`

    connection.query(query, tableName, (error, result) => { // sends queries
        connection.end();                                   // closes connection
        if (error) throw error;
        console.log(result);
    });
});

Result:

[
    { id: 1, name: 'John',  role: 'admin' },     
    { id: 2, name: 'Chris', role: 'moderator' },
    { id: 3, name: 'Kate',  role: 'user' },      
    { id: 4, name: 'Denis', role: 'moderator' } 
]

2. Database preparation

create_tables.sql file:

CREATE TABLE `users` (
	`id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
	`name` VARCHAR(100) NOT NULL,
	`role` VARCHAR(15) NOT NULL,
	PRIMARY KEY (`id`)
)
ENGINE=InnoDB;

insert_data.sql file:

INSERT INTO `users`
	(`name`, `role`)
VALUES
	('John', 'admin'),
	('Chris', 'moderator'),
	('Kate', 'user'),
	('Denis', 'moderator');

See also:

1. Node.js - MySQL Insert query

2. Node.js - MySQL Delete query

3. Node.js - MySQL Update query