The  goal of the project is to implement a “prototype” database system  application / ERD diagram for an eCommerce social-network system called  UCOnline where users can explore information about books/music/software,  rate your purchase, identify purchase price and see ratings of their  friends.  The  project will require you to complete the assignment individually. Below  you will find the ERD deliverable requirements. There are two parts to  the assignment. You must create a diagram using a diagramming tool AND  provide a written text-based document explaining your relationship  mapping (systems analysis use case document). The assignment is worth 30  points. See rubric for grading scheme.  BUSINESS REQUIREMENTS ACROSS ALL ASSIGNMENTS  You will work with book/music/media information, user information, ratings of books, and users’ social network  

• Each  book has an id, title, publication date, publisher, ISBN, functional  category, page count, price (publisher), and product description
• There are 3 categories of book: fiction, non-fiction, and specialty
• There are 2 categories of music: digital and media-based
• An author can write one or more books.
• A musician can be a solo artist, part of a group, or both
• An author can also be associated with one or more publishers.
• A musician/group/act can be associated with one or more music houses
• An author’s book can have one or more editions.
• A song and or album can have more than one version/edition (i.e. EP, LP, CD, DVD etc)
• A publisher can have many authors and many books.
• A record company can have many artists associated and many albums associated with it. 
• A record company can also be the publishing company (i.e. self-publishing)
• Many  ISBNs can also be associated with a given publisher but only one ISBN  per form of medium (ie the ISBN is the PK no matter what).
• An author can write many books.
• An artist can write many songs, albums etc.

UCOnline needs  to keep track of user ratings for each item sold in the online store  (e.g., 1-5 and 1 for ‘Dislike’, to 5, for ‘Awesome!’). A particular user rates a particular item at a given time. A user CANNOT rate the same multiple times unless there are multiple editions of the item. Each edition can be rated separately. Each  user who submits a rating will be identified by a unique id and has a  name, gender, age, and location. Nothing is anonymous. 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).