Restart Docker Compose with update to database - mysql

Question

I've been working with a simple MySQL table using Docker Compose that only included ID and NAME column. I attempted to update my myDb.sql file that initially creates the table like this:
CREATE TABLE `Person` (
`id` int(11) NOT NULL,
`firstName` varchar(50) NOT NULL, // updated this column
`lastName` varchar(50) NOT NULL // added this column
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
I updated the NAME column to firstName, and added a lastName column.
I then stopped the Docker containers by running DOCKER-COMPOSE STOP.
I then restarted the Docker containers by running DOCKER-COMPOSE UP. I even tried DOCKER-COMPOSE RESTART.
The error message I was able to print in the console was this:
SELECT '', id, `firstName` From Person<br>Unknown column 'firstName' in 'field list'
This leads me to believe that I did not restart Docker Compose correctly.
How do I restart Docker Compose so that it runs the CREATE TABLE command?
Edit
Here is my docker-compose.yml file:
version: "3.7"
services:
www:
build: .
ports:
- "8001:80"
volumes:
- ./www:/var/www/html/
links:
- db
networks:
- default
db:
image: mysql:5.7.13
ports:
- "3306:3306"
environment:
MYSQL_DATABASE: myDb
MYSQL_USER: user
MYSQL_PASSWORD: test
MYSQL_ROOT_PASSWORD: test
volumes:
- ./dump:/docker-entrypoint-initdb.d
- persistent:/var/lib/mysql
networks:
- default
phpmyadmin:
image: phpmyadmin/phpmyadmin
links:
- db:db
ports:
- 8000:80
environment:
MYSQL_USER: user
MYSQL_PASSWORD: test
MYSQL_ROOT_PASSWORD: test
volumes:
persistent:
My Dockerfile looks like this:
FROM php:7.0.30-apache
RUN docker-php-ext-install mysqli

Answer 1

The docker-entrypoint-initdb.d mechanism only runs the first time a database container starts up, with an empty database. You'll need to explicitly docker-compose rm your containers after you docker-compose stop them to cause the current database to be deleted, and then a new empty table will be created in a new empty database.
If you need to preserve the data in an existing database, you are looking for a mechanism called a migration. The various Docker database images don't directly have migration support; this is almost always something that is packaged with your application-level database library (Ruby on Rails and Python's SQLAlchemy both have migration facilities, for instance).
Once you have a migration system anyways, it's probably better to just use that to create the initial database tables. docker-entrypoint-initdb.d makes a little more sense for database-level setup like creating initial users or loading a seed database dump, but in practice you will always need a migration system for changes like what you're describing.

Answer 2

Do docker-compose down whenever you update your schema, it will remove containers and docker network and do docker-compose up to bring your environment with your new schema. Hope it helps. If not, try updating to latest mysql image, the image you are using is almost 3 years old.

Answer 3

So I was thinking that restarting docker-compose would automatically run the CREATE TABLE query in the myDb.sql file. As indicated above, I changed the name of 'name' column to 'firstName' and added a column called 'lastName'.
Again, I am not sure if there was a command that actually does this, but in the end, I was able to alter the table in phpmyadmin. Once I altered the table there, now I am getting data back to the page with no errors.