Database

The database used is a lightweight MariaDB. It is instantiated in a separate docker container defined in the docker-compose.yml file.

Structure

The Sales Point main functionality is based on the following database:

• Category is used to order the articles on the new order screen.
• KitchenStation defines who is preparing the article (Grill, Fritteuse, ..)
• A cart or order is defined by its line items. These handle the articles and their count.
• The printer table is missing on the image.

Migrations

When changing the database structure, Ruby on Rails uses Migrations. Any existing database can be migrated using /bin/rails db:migrate. See also the official documentation.

First time setup

When spinning up any mariadb container the first time, a user and empty database must be created. For successive startups these settings are stored in a docker volume. To do so login into the docker container and then:

• login with the root user:mariadb -p, enter root password from docker-compose
• create a user and database according to the env setting (see config/database.yml)
• create a new user: create user <dptdb> identified by '<password>';
• create a new empty database: create database dptDev;
• add user to database: grant all privileges on dptDev.* to dptdb@'%';

Initialize a new database

To initialize a new and clean database simply use the rails command bin/rails db:setup. This also seeds the database with the defined seeds in db/seeds.rb. Prior to this, the database and user has to be created inside the docker container.

Backup the data

Use the mariadb-dump tool in the container:

mariadb-dump  -p -x --databases dptDev > database.sql
mariadb-dump  -pASDF -x --databases dptDev > database.sql # where ASDF is the password of the user

Then copy it from the docker container to the host with

sudo docker cp sales-point_devcontainer-db-1:/home/database.sql ./database.sql