I use the official mysql base image from Docker Hub to create mysql database. But by default it only creates one database. I want to create another database.
mysql image actually provides a way to do this. Reference the official doc: https://github.com/docker-library/docs/tree/master/mysql Under “Initializing a fresh instance” section.
So we just need to create a .sql file with create database command, and mount this file as volume to docker-entrypoint-initdb.d folder inside mysql container.
This is my docker-compose.yml file:
services: db: image: mysql # Pull mysql image from Docker Hub environment: # Set up mysql database name and password MYSQL_DATABASE: development MYSQL_ROOT_PASSWORD: password ports: # Set up ports exposed for other containers to connect to - "3306" volumes: # Mount relative path source folder on host to absolute path destination folder on docker container - ./docker-entrypoint-initdb.d:/docker-entrypoint-initdb.d web: build: . # Look in the current directory for a Dockerfile and build images using it depends_on: # Link web container to db container - db environment: # Set up environment variables MYSQL_DATABASE: development MYSQL_ROOT_PASSWORD: password RAILS_ENV: docker ports: - "3000:3000" # Forwards the exposed port 3000 on the container to port 3000 on the host machine
We create init.sql file inside docker-entrypoint-initdb.d folder, and use “volumes” to mount this folder to docker-entrypoint-initdb.d inside mysql container, so that mysql service will have access to all the files in docker-entrypoint-initdb.d folder on host. The content of init.sql file:
CREATE DATABASE test;
After we run
It will boot up db and web service. The db service will be a mysql container, which have two databases: develop and test.