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PostgreSQL - search for NULL values in multiple columns

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Created by:
Tehya-Blanchard
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In this article, we would like to show you how to find rows with NULL values in many columns in PostgreSQL.

Quick solution:

SELECT *
FROM "table_name" 
WHERE "column1" IS NULL AND "column2" IS NULL AND "columnN" IS NULL;
SELECT *
FROM "users"
WHERE COALESCE("column1", "column2") IS NULL;

Practical example

To show how to find rows with NULL values in many columns, we will use the following table:

PostgreSQL - select rows with NULL values in multiple columns - example data
PostgreSQL - select rows with NULL values in multiple columns - example data

Note:

At the end of this article you can find database preparation SQL queries.

Example 1

In this example, we will select all rows with NULL value both in email and department_id column using IS NULL and AND keywords.

Query:

SELECT *
FROM "users"
WHERE "email" IS NULL AND "department_id" IS NULL;

Result:

PostgreSQL - select rows with multiple NULL column values - result
PostgreSQL - select rows with multiple NULL column values - result

Example 2

In this example, we will select all rows with NULL value both in email and department_id column using COALESCE() function.

Query:

SELECT *
FROM "users"
WHERE COALESCE("email", "department_id") IS NULL;

Result:

PostgreSQL - select rows with multiple NULL column values - result
PostgreSQL - select rows with multiple NULL column values - result

Database preparation

create_tables.sql file:

CREATE TABLE "users" (
	"id" SERIAL,
	"name" VARCHAR(50) NOT NULL,
	"surname" VARCHAR(50) NOT NULL,
	"email" VARCHAR(100),
	"department_id" INTEGER,
    "salary" DECIMAL(15,2) NOT NULL,
	PRIMARY KEY ("id")
);

insert_data.sql file:

INSERT INTO "users"
	( "name", "surname", "email", "department_id", "salary")
VALUES
	('John', 'Stewart', 'john@email.com', 1, '3512.00'),
	('Chris', 'Brown', 'chris@email.com', 2, '1344.00'),
	('Kate', 'Lewis', NULL, 3, '6574.00'),
	('Ailisa', 'Gomez', 'ailisa@email.com', 2, '6500.00'),
	('Gwendolyn', 'James', NULL, NULL, '4200.00'),
	('Simon', 'Collins', NULL, 4, '3320.00'),
	('Taylor', 'Martin', NULL, NULL, '1500.00'),
	('Andrew', 'Thompson', 'andrew@email.com', NULL, '2100.00');

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