Languages
[Edit]
EN

Node.js - MySQL SELECT DISTINCT statement

0 points
Created by:
Cassia-Mendoza
415

In this article, we would like to show you how to make MySQLΒ SELECT DISTINCT statement in Node.js.

example data used with SELECT DISTINCT statement
Example data used with SELECT DISTINCT statement - HeidiSQL

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

Practical example

const mysql = require('mysql');

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

connection.connect(error => {
    if (error) throw error;
    const query ='SELECT DISTINCT `country` FROM `users`';

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

Result:

β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”¬β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”
β”‚ (index) β”‚  country  β”‚
β”œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”Όβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€
β”‚    0    β”‚  'Spain'  β”‚
β”‚    1    β”‚  'Italy'  β”‚
β”‚    2    β”‚ 'Vietnam' β”‚
β”‚    3    β”‚ 'Poland'  β”‚
β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”΄β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜

Database preparation

create_tables.sqlΒ file:

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

insert_data.sqlΒ file:

INSERT INTO `users`
	(`name`, `country`)
VALUES
    ('Tom', 'Poland'),
    ('Chris', 'Spain'),
    ('Jack', 'Spain'),
    ('Kim', 'Vietnam'),
    ('Marco', 'Italy'),
    ('Kate', 'Spain'),
    ('Nam', 'Vietnam');

Node.js - MySQL

Native Advertising
πŸš€
Get your tech brand or product in front of software developers.
For more information Contact us
Dirask - we help you to
solve coding problems.
Ask question.

β€οΈπŸ’» πŸ™‚

Join