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The goal of the project is develop ERD for database system application of an eCommerce social-network system called xyz where users can explore information about books/music/software, rate your purchase, identify purchase price and see ratings of their friends.

Below you will find the ERD deliverable requirements.

There is also a social network between users. Users can send communication requests (i.e. instant messages/emails) to other users. Such requests can be accepted or ignored. Once accepted, the two users are considered ‘book buddies.’ If ignored, the user can send the request again. We want to add a store when the requests were sent (timestamp), the result of the requests and when the request was answered (timestamp).