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                        Node.js - PostgreSQL ORDER BY
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                                In this article, we would like to show you how to use SQL ORDER BY in Node.js with Postgress.
Note: at the end of this article you can find database preparation SQL queries.
Ascending order:
In this section you can find example that orders results using A-Z direction.
const { Client } = require('pg');
const client = new Client({
    host: '127.0.0.1',
    user: 'postgres',
    database: 'database_name',
    password: 'password',
    port: 5432,
});
const fetchUsers = async (orderBy) => {
    const query = `SELECT * 
                   FROM "users"
                   ORDER BY $1`; // it abbreviated form to: ORDER BY $1 ASC
    try {
        await client.connect();                                // creates connection
        const { rows } = await client.query(query, [orderBy]); // sends queries
        console.log(rows);
    } catch (error) {
        console.error(error.stack);
    } finally {
        await client.end();                                    // closes connection
    }
};
fetchUsers('name');
Result:
[
    { id: 2, name: 'Chris', role: 'moderator' },
    { id: 4, name: 'Denis', role: 'moderator' },
    { id: 1, name: 'John',  role: 'admin' },
    { id: 3, name: 'Kate',  role: 'user' }
]
Descending order:
In this section you can find example that orders results using Z-A direction.
const { Client } = require('pg');
const client = new Client({
    host: '127.0.0.1',
    user: 'postgres',
    database: 'my_database',
    password: 'password',
    port: 5432,
});
const fetchUsers = async (orderBy) => {
    const query = `SELECT * 
                   FROM "users"
                   ORDER BY $1 DESC`;
    try {
        await client.connect();                                // gets connection
        const { rows } = await client.query(query, [orderBy]); // sends queries
        console.log(rows);
    } catch (error) {
        console.error(error.stack);
    } finally {
        await client.end();                                    // closes connection
    }
};
fetchUsers('id');
Result:
[
    { id: 4, name: 'Denis', role: 'moderator' },
    { id: 3, name: 'Kate',  role: 'user' },
    { id: 2, name: 'Chris', role: 'moderator' },
    { id: 1, name: 'John',  role: 'admin' }
]
Database preparation
create_tables.sql file:
CREATE TABLE "users" (
	"id" SERIAL,
	"name" VARCHAR(100) NOT NULL,
	"role" VARCHAR(15) NOT NULL,
	PRIMARY KEY ("id")
);
insert_data.sql file:
INSERT INTO "users"
	("name", "role")
VALUES
	('John', 'admin'),
	('Chris', 'moderator'),
	('Kate', 'user'),
	('Denis', 'moderator');
                                    
                                    
                                