Working with LOWER in MySQL
05.13.2022
Intro
MySQL provides the lower function to transform a string into all lower case letters. In this article, we will learn how to use LOWER in MySQL.
The Syntax
The basic syntax of a LOWER is as follows:
SELECT LOWER(string);- string: The string or varchar you want to lower case.
Getting Setup
We will be using docker in this article, but feel free to install your database locally instead. Once you have docker installed, create a new file called docker-compose.yml and add the following.
version: '3'
services:
db:
image: mysql:latest
container_name: db
environment:
MYSQL_ROOT_PASSWORD: root_pass
MYSQL_DATABASE: app_db
MYSQL_USER: db_user
MYSQL_PASSWORD: db_user_pass
ports:
- "6033:3306"
volumes:
- dbdata:/var/lib/mysql
phpmyadmin:
image: phpmyadmin/phpmyadmin
container_name: pma
links:
- db
environment:
PMA_HOST: db
PMA_PORT: 3306
PMA_ARBITRARY: 1
restart: always
ports:
- 8081:80
volumes:
dbdata:Next, run docker-compose up.
Now, navigate to http://localhost:8081/ to access phpMyAdmin. Then log in with the username root and pass root_pass.
Click the SQL tab and you are ready to go.
Basic Example
The simple example is to lower case a string literal. Here is an example.
select lower('Hello World!') as lower_string;| lower_string |
|---|
| hello world! |
Lower on a Table Column
We can also run lower on a column. Below we create an employee table.
CREATE TABLE employees (
first_name VARCHAR (50) NOT NULL,
last_name VARCHAR (50) NOT NULL
);
insert into employees (first_name, last_name)
values
('Keith', 'Holliday'),
('Jon', 'Doe'),
('Jane', 'Doe');We can now run the lower function on the columns.
select
lower(first_name) as FirstName,
lower(last_name) as LastName
from employees e;| FirstName | LastName |
|---|---|
| keith | holliday |
| jon | doe |
| jane | doe |