On MySQL, If multiple users provision the same project key in the same time, it's possible to create multiple projects with the same key.
In 5.2, PROJECTS.KEE is unique, but not on MySQL.
To prevent inserting multiple projects with the same key, here's what we should do :
- Insert the new project with the given key
- In another transaction, select projects with this key (order by their ids), and remove them all expect the first one