Common Expenses: ER Schema

This is the ER schema for the database of Common Expenses application:

ER Schema
ER Schema

The schema itself should be quite self-explaining anyway here are the main points:

  • meta_ts and meta_user are logging data they represent date and user of tuple creation.
  • OneToMany relationship between Project and Expense
  • OneToMany relationship between User and Share
  • OneToMany relationship between Expense and Share
  • ManyToMany relationship between User and Project, there are a join table (Partecipate) for this relationship which hold also the leader of a project.

I’m going to make Hibernate generate the database form me so I’m quite sure the final schema will be slighty different from the one above.

Common Expenses: Working Place

Face a new project imply selecting the tools/technologies you’ll be using during developement.

Here is a brief excursus on what I’ll use.

IDE: Eclipse

Eclipse is a very powerfull IDE, I’m using it every day at work for PHP developing that’s why i feel so comfortable with it. Furthermore Eclipse has born for Java developing so i thing this is the right choice.


Because it’s free and I know it quite well since I’m using it for more than 6 years, I could choose SQL Server (the one we use at work) but since it is not free and I’m developing on a Mac that’s it. Moreover MySQL has MySQL Workbench which is a very usefull tool form designing/managing databases.

ORM: Hibernate

This is a project requirement, but i would have use it the same as it seems the most used out there and i want to learn it.