Documentation bug
Created by: hyder
In the guide: https://github.com/gitlabhq/gitlabhq/blob/4-0-stable/doc/install/installation.md, under Install Gems, we can see the following:
For mysql db
sudo -u gitlab -H bundle install --deployment --without development test postgres
Or For postgres db
sudo -u gitlab -H bundle install --deployment --without development test mysql
The database option should be the other way round.