Creating a docker mysql container with a prepared database scheme

I had to do this for tests purposes.

Here's how i did by leveraging the actual MySQL/MariaDB images on dockerhub and the multi-stage build:

FROM mariadb:latest as builder

# That file does the DB initialization but also runs mysql daemon, by removing the last line it will only init
RUN ["sed", "-i", "s/exec \"$@\"/echo \"not running $@\"/", "/usr/local/bin/docker-entrypoint.sh"]

# needed for intialization
ENV MYSQL_ROOT_PASSWORD=root

COPY setup.sql /docker-entrypoint-initdb.d/

# Need to change the datadir to something else that /var/lib/mysql because the parent docker file defines it as a volume.
# https://docs.docker.com/engine/reference/builder/#volume :
#       Changing the volume from within the Dockerfile: If any build steps change the data within the volume after
#       it has been declared, those changes will be discarded.
RUN ["/usr/local/bin/docker-entrypoint.sh", "mysqld", "--datadir", "/initialized-db", "--aria-log-dir-path", "/initialized-db"]

FROM mariadb:latest

COPY --from=builder /initialized-db /var/lib/mysql

Full working example here : https://github.com/lindycoder/prepopulated-mysql-container-example

You should put your init script in a directory mounted as /docker-entrypoint-initdb.d - see "Initializing a fresh instance" section in the MySQL Docker image docs.

Credits to @Martin Roy

Made minor changes to work for mysql...

Content Dockerfile

FROM mysql:latest as builder

# That file does the DB initialization but also runs mysql daemon, by removing the last line it will only init
RUN ["sed", "-i", "s/exec \"$@\"/echo \"not running $@\"/", "/usr/local/bin/docker-entrypoint.sh"]

# needed for intialization
ENV MYSQL_ROOT_PASSWORD=root

COPY setup.sql /docker-entrypoint-initdb.d/

# Need to change the datadir to something else that /var/lib/mysql because the parent docker file defines it as a volume.
# https://docs.docker.com/engine/reference/builder/#volume :
#       Changing the volume from within the Dockerfile: If any build steps change the data within the volume after
#       it has been declared, those changes will be discarded.
RUN ["/usr/local/bin/docker-entrypoint.sh", "mysqld", "--datadir", "/initialized-db"]

FROM mysql:latest

COPY --from=builder /initialized-db /var/lib/mysql

Content setup.sql

CREATE DATABASE myexample;

USE myexample;

CREATE TABLE mytable (myfield VARCHAR(20));

INSERT INTO mytable VALUES ('Hello'), ('Dolly');

Full working example here : https://github.com/iamdvr/prepopulated-mysql-container-example