PostgreSQL provides the RTRIM function to remove extra white space to the right of the string. In this article, we will learn how to use RTRIM with PostgreSQL.
The basic syntax of a RTRIM is as follows:
SELECT RTRIM(string_name, length);
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: 'postgres:latest' ports: - 5432:5432 environment: POSTGRES_USER: username POSTGRES_PASSWORD: password POSTGRES_DB: default_database volumes: - psqldata:/var/lib/postgresql phpmyadmin: image: phpmyadmin/phpmyadmin links: - db environment: PMA_HOST: db PMA_PORT: 3306 PMA_ARBITRARY: 1 restart: always ports: - 8081:80 volumes: psqldata:
Now, navigate to
http://localhost:8081/ to access phpMyAdmin. Then log in with the username
root and pass
Click the SQL tab and you are ready to go.
The basic example is straight forward. We can pass a string into the RTRIM function and it will remove the white space on the right.
SELECT RTRIM('Hello World! ');
|RTRIM('Hello World! ')|
That's the gist of using the RTRIM function. We can also use RTRIM on a table. If you would like to try that, let's first set up a table.
We start by creating an employee table to work with.
CREATE TABLE employees ( first_name VARCHAR (50) NOT NULL, last_name VARCHAR (50) NOT NULL );
Next, we can insert some data with extra right spaces
insert into employees (first_name, last_name) values ('Keith ', 'Holliday'), ('Jon ', 'Doe'), ('Jane ', 'Doe');
And, we can preview the data like so.
SELECT * FROM employees;
Now that we are set up, we can use RIGHT on our columns.
SELECT RTRIM(first_name) as first_name FROM employees;