Postgresql provides the
CHR function to allow us to convert numbers into characters. The function is simple, but helpful in string processing. In this article, we will learn how to use CHR in postgresql.
The basic syntax of a CHR is as follows:
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.
For a list of codes, we can use the following page: https://en.wikipedia.org/wiki/List_of_Unicode_characters. The decimal column will tell us which number to use in our function.
Let's start with a quick example of selecting a capital
We aren't restricted to the Latin alphabet. Here is an example of using the