Hi everybody
I just signed up for dBforums.
I have an assignment related to Twitter.com.
I prepared an ER diagram for Twitter database and attached them.

Basic points to capture in the assignment are as follows:

1. Members signing up with a profile and posting information, tweets,
2. Members subscribing to different sources (members) and accessing the tweets posted by these sources.
3. Members restricting delivery of their tweets to those in their circle of friends.

I designed files HW_1 and HW_2 with a similar approach but I changed my approach in HW_3.

Here is my issues:

- I could not be sure whether I achieved to capture delivery restriction in
any of my diagrams.

- My diagrams looked so simple to me.Did I miss anything?
Eventually Twitter is a social networking website and I think I might have
overlooked some relations.

- I wonder if my approaches are promising or just crap

Any advice and help about my designs and missing points are appreciated.

Best Regards,