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Node.js - PostgreSQL - find row with null value in column

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Created by:
Dirask Admin - MR
1340

In this article, we would like to show you how to find the row with a null value in a column in the PostgreSQL database using Node.js.

Node.js - PostgreSQL - find row with null value in column
Data used in the example - HeidiSQL

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

const { Client } = require('pg');

const client = new Client({
    host: '127.0.0.1',
    user: 'postgres',
    database: 'database_name',
    password: 'password',
    port: 5432,
});

const getRowWithoutEmail = async () => {
    const query = `SELECT * 
				   FROM "users"
				   WHERE "email" IS NULL;`;
    try {
        await client.connect();  // creates connection
        const { rows } = await client.query(query); // sends query
		console.table(rows);
    } catch (error) {
        console.error(error.stack);
    } finally {
        await client.end();      // closes connection
    }
};

getRowWithoutEmail();

Result: 

┌─────────┬────┬─────────────┬───────────┬───────┐
│ (index) │ id │    name     │  surname  │ email │
├─────────┼────┼─────────────┼───────────┼───────┤
│    0    │ 2  │   'Chris'   │  'Brown'  │ null  │
│    1    │ 3  │   'Kate'    │  'Lewis'  │ null  │
│    2    │ 5  │ 'Gwendolyn' │  'James'  │ null  │
│    3    │ 6  │   'Simon'   │ 'Collins' │ null  │
│    4    │ 7  │  'Taylor'   │ 'Martin'  │ null  │
└─────────┴────┴─────────────┴───────────┴───────┘

Database preparation

create_tables.sql file:

CREATE TABLE "users" (
	"id" SERIAL,
	"name" VARCHAR(50) NOT NULL,
	"surname" VARCHAR(50) NOT NULL,
	"email" VARCHAR(50),
	PRIMARY KEY ("id")
);

insert_data.sql file:

INSERT INTO "users"
	( "name", "surname", "email")
VALUES
	('John', 'Stewart', 'john@email.com'),
	('Chris', 'Brown', NULL),
	('Kate', 'Lewis', NULL),
	('Ailisa', 'Gomez', 'ailisa@email.com'),
	('Gwendolyn', 'James', NULL),
	('Simon', 'Collins', NULL),
	('Taylor', 'Martin', NULL),
	('Andrew', 'Thompson', 'andrew@email.com');

Native SQL query (used in the above example):

SELECT * 
FROM "users"
WHERE "email" IS NULL

Node.js - PostgreSQL - Problems

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