Completeness of the system
| User | Messages | Drafts | File | |
| Create new user | C | |||
| Update user informations | U | |||
| Delete user accout | D | |||
| Create a message | CU | CU | ||
| Create file | C | |||
| Delete file | D | |||
| Change file | U | |||
| Send a message |
U | U | ||
| Add new recipients to messages |
R | U | U | |
| Attach files to messages |
U | U | R | |
| Delete drafts |
D | |||
| Save drafts |
U | |||
| View recipients addresses |
R | |||
| View sended messages |
R | |||
| Delete message | D | |||
| View groups of recipients |
R | |||
| View all my drafts | R |
[Note for the author: take the CRUD matrix and fill in the gaps in functions or entities ]