Question

I am trying to implement the Finanace application with many classes (wrt java).
I have this case

class User {

String name;
Int age;
Collection<Accounts> accounts;

Interface Account

Then following classes implements interface

1. Saving Account
2. Fixed Account
3. Insurance Account

The account will have User Object

As i am java person , i want to know can i use collection of Account objects in my user class.

Also how will Django handle the relationships and make database tables if i use collection

Answer 1

You probably want to use django.contrib.auth, which already provides a User model, so you’ll want to write a model to store additional user information, instead of defining a new User model. Django models (generally) represent database tables, each attribute represents a database field. You define your models and their relationships, and Django provides a nice database-access API. You generally don’t “store collection of Account objects”, you create another model and use a ForeignKey field to describe the relationship between the models.

class UserProfile(models.Model):
    user = models.ForeignKey(User, unique=True)
    age = models.IntegerField()

class Account(models.Model):
    user_profile = models.ForeignKey('UserProfile')

And then you’d use Django’s API to work with your models:

profile = User.objects.get(id=1).get_profile() # get user's profile
profile.account_set.all() # get all accounts associated with user's profile
acct = Account() # create a new account
profile.account_set.add(acct) # add a new account to the user's profile

Django’s tutorial is a good place to start, if you want to use Django for this project you need some concept of how things are done. It’s also might be a good idea to learn python first.