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Node.js - PostgreSQL Update query

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Created by:

Mikolaj

519

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

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

1. `UPDATE` query example - async-await

Edit

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const { Client } = require('pg');
​
const client = new Client({
    host: '127.0.0.1',
    user: 'postgres',
    database: 'database_name',
    password: 'password',
    port: 5432,
});
​
const updateUser = async (userName, userRole, userId) => {
    const query = `UPDATE "users" 
                   SET "name" = $1, "role" = $2 
                   WHERE "id" = $3`;
    try {
        await client.connect();          // gets connection
        await client.query(query, [userName, userRole, userId]); // sends queries
        return true;
    } catch (error) {
        console.error(error.stack);
        return false;
    } finally {
        await client.end();              // closes connection
    }
};
​
updateUser('Christopher', 'admin', '2').then(result => {  // userName, userRole, userId
    if (result) {
        console.log('User updated');
    }
});

Before:

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

After:

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

2. Database preparation

Edit

create_tables.sql file:

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CREATE TABLE "users" (
    "id" SERIAL,
    "name" VARCHAR(100) NOT NULL,
    "role" VARCHAR(15) NOT NULL,
    PRIMARY KEY ("id")
);

insert_data.sql file:

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