PostgreSQL - find row with null value in one of many columns

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Created by:

Kelly

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In this article, we would like to show you how to find rows with NULL value in one of many columns in PostgreSQL.

Quick solution:

SELECT *
FROM "table_name" 
WHERE "column1" IS NULL OR "column2" IS NULL OR "columnN" IS NULL;

SELECT *
FROM "table_name"
WHERE "column1"+"column2"+"columnN" IS NULL;

SELECT *
FROM "table_name"
WHERE CONCAT("column1", "column2", "columnN") IS NULL;

Practical example

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

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 - `IS NULL` & `OR`

In this example, we will select rows from users table with NULL value in email OR department_id column.

Query:

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

Result:

Example 2 - `+` & `IS NULL`

In this example, we will select rows from users table with NULL value in email or department_id column using + operator.

Query:

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

Result:

Example 3 - `CONCAT()` function

In this example, we will select rows from users table with NULL value in email or department_id column using CONCAT() function.

Query:

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

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');