MySql provides the IN operator to match a list of values. Rather than writing a list of OR clauses we can use the IN as a shortcut. For example, say we have a list of cities and addresses. We can check if an address is located in our list using the IN operation. In this article, we will learn how to use th eIN operator.
The basic syntax of IN is as follows:
[value] IN (val1, val2, val3, …)
Value is the column we want to compare and the list to the right is the list of values we will accept.
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:
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.
In this article, we will need some data to work with. If you don't understand these commands, don't worry, we will cover them in later articles.
We will be using the sample db provided here: https://dev.mysql.com/doc/sakila/en/. However, we will only enter what we need rather than import the whole db.
With the SQL tab open (or your own sql cli going), let's first create our DB and select it.
create DATABASE if not EXISTS sakila; USE sakila;
Next, let's create an
CREATE TABLE actor ( actor_id SMALLINT UNSIGNED NOT NULL AUTO_INCREMENT, first_name VARCHAR(45) NOT NULL, last_name VARCHAR(45) NOT NULL, last_update TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, PRIMARY KEY (actor_id), KEY idx_actor_last_name (last_name) ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
And finally, let's enter a few rows.
INSERT INTO actor VALUES (1,'PENELOPE','GUINESS','2006-02-15 04:34:33'), (2,'NICK','WAHLBERG','2006-02-15 04:34:33'), (3,'ED','CHASE','2006-02-15 04:34:33'), (4,'JENNIFER','DAVIS','2006-02-15 04:34:33'), (5,'JOHNNY','LOLLOBRIGIDA','2006-02-15 04:34:33'), (6,'BETTE','NICHOLSON','2006-02-15 04:34:33'), (7,'GRACE','MOSTEL','2006-02-15 04:34:33'), (8,'MATTHEW','JOHANSSON','2006-02-15 04:34:33'), (9,'GRACE','JOHANSSON','2006-02-15 04:34:33')
Let’s say want to select actors with either last name GUINESS or CHASE. We could use multiple OR clauses.
SELECT * FROM actor WHERE last_name = 'GUINESS' OR last_name = 'CHASE';
If we needed to add more countries, the OR clauses can get long. Instead, we can replace that with the IN operator.
SELECT * FROM actor WHERE last_name IN ('GUINESS', 'CHASE');