- Records that Vlnce doesn't want to buy can be left behind to go in the ve-foradollar bin. 4. List some major security rules for the database. There are very few security concerns for Vince's database. If he starts collecting customer information, that data should be secured. If he eventually goes online the database will have to be protected against accidental or malicious attack. 5. Take a look at each of the forms and make a list of all the nouns in them. Do the same for the interview, the questionnaire and the Job Shadow Report. Then set up some preliminary entities and attributes. Nouns: Seller's Name, Seller's Phone Number, Album, Notes, Condition, Paid, Date, Customer, Price, Tax, Total Entities and attributes: Seller (Seller's Name, Seller's Phone Number, Album, Notes, Condition, Paid) Sale (Date, Customer, Album, Price, Tax, Total) Inventory (Album, Paid, Price, Condition)Inventory is implied from the discussions, interviews and purpose of the database 6. Identify some candidate keys. For Seller, Seller's Name or Phone Number For Sale, maybe Date and Album combined, though that is not guaranteed to be unique For Inventory, possibly Album though that is not guaranteed to be unique 7. Documentation: Store the list of the requirements and business rules in your database notebook Vince's Vinyl : Chapter 4 1. Review all the requirements and rules that you have gathered from your interviews and after reviewing Vince's records. 2. Dene your entities and attributes and the relations that exist between them. 3. Create a logical model using crow's feet notation in Visio or hand draw it on graph paper, if you prefer. 4. Add all the entities and their attributes. You don't need to worry about data types for now. 5. Identify the key fields for each entity and the foreign keys. 6. Analyze the diagram. Identify which role (i.e., domain, linking, lookup, weak) each entity plays in your database. IGNORE 7. Have another student or a group review it for the following: a. Are all the major components of Vinces Vinyl business model represented by domain entities? b. Does each entity contain the appropriate attributes to frilly describe it and meet the business rules you have gathered so for? c. Does every entity have an appropriate primary key dened? d. Are all many-to-many relationships resolved into one-tomany relationships by linking tables? e. Are the relationships valid (no cross-relationships)? Is the appropriate entity defined as the one side of a one-to-many relationship? Do the tables have appropriate foreign keys? Also Check for other such issues. f. Are lockup tables used for attributes that have a set list of values? 8. Documentation: Be sure to store your ERDs in your database notebook. Below is one possible ERD. The Artist entity and its linking table are optional. Since Sellers could also be customers, it would be possible to approach the problem by creating a Person entity that contains both customers and sellers. This will be suggested in Chapter 5 on Normalization