PostgreSQL - LOWER() function example

In this article, we would like to show you how to use LOWER() function in PostgreSQL.

Quick solutions:

SELECT LOWER('SOME TEXT...');

SELECT LOWER("column_name") FROM "table_name";

Practical example

To show how the LOWER() function works, we will use the following table:

Note:

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

Example

In this example, we will display all the names from users table in lowercase.

Query:

SELECT LOWER("name") AS "Lowercase names" FROM "users";

Output:

Database preparation

create_tables.sql file:

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

 insert_data.sql file:

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