Link table logic

Rails
1

Hi again! In my application, I have a Users model and an Events model. I
also have a link model to link an event to a user. However, a user can
be linked to an event in a number of ways - e.g. they can have created
an event, or subscibed to an event.

Now, the link table for both these relationships will effectively
contain the same information - an event ID and a user ID.

How is this link represented in the rails model?

For example, can I say:

class User < ActiveRecord::Base
has_many :created_events
has_many :subscribed_events
has_many :events, :through => :created_events, :subscribed_events

or something to that effect? Also, how would User.events work in this
case? The logic doesn’t seem quite correct!

Have I went about my database design in the wrong way?

As always, any help is greatly appreciated - I hope I have made myself
clear!

Cheers,

Mick

2

case? The logic doesn’t seem quite correct!

Have I went about my database design in the wrong way?

As always, any help is greatly appreciated - I hope I have made myself
clear!

Untested, but fairly sure it will work:

Fetch the events for both relationships, then just add them:

def events
cr_ev=created_events.events
sb_ev=subscribed_events.events
total = cr_ev + sb_ev
total.uniq
end

Best regards

Peter De Berdt

3

Could a potential database design be as follows:

events - has unique event ID
users - has unique user ID

user_events - has event ID and user ID as a foreigh key

user_event_creation - has unique ID and user_event_id as foreign key
user_event_subscription - has unique ID and user_event_id as foreign key

any ideas?