NO NEED TO WRITE EXPLANATION, JUST SAY WHAT THE ANSWER IS AND I CAN FIGURE OUT WHY ON MY OWN SO I CAN SOLIDIFY THE REASONING BETTER. AGAIN, JUST...

NO NEED TO WRITE EXPLANATION, JUST SAY WHAT THE ANSWER IS AND I CAN FIGURE OUT WHY ON MY OWN SO I CAN SOLIDIFY THE REASONING BETTER. AGAIN, JUST ANSWERS, NO EXPLANATION

19.         Assume you are dealing with a purchasing database involving a single table. This table contains information on          the customer, sale, and items purchased; the sales order number is the primary key. Using this database design, as you remove old sales information, you may lose information on some of your customers. This is an example              of

                                               A. a hidden dependency                                                              B. a deletion anomoly

                                               C. an update anomoly                                                   D. an insertion anomoly

20.         Which of the following is true about the following BOOK dependency diagram where ISBN is the primary key?

               Where for BOOK, ISBN goes into Title and Publisher; Publisher goes into Address

                               A. the relation is in 3NF

                               B. there exists one transitive dependency

                               C. there exists one partial dependency

                               D. there exists two partial dependencies

21.         Which of the following is true about a simple primary key?

               A. It can have duplicate values

               B. It can have a null value

               C. It is not mandatory for a table to have a primary key

               D. It uniquely identifies each row in a table

22.         An attribute that must have a value for every entity (or relationship) instance is a(n):

                               A. composit attribute                                                    B. required attribute

                               C. optional attribute                                                      D. multivalued attribute

23.         A student can attend five classes, each with a different professor. Each professor has 30 students. The                relationship of students to professors is a _________ relationship

                               A. one-to-one                                                  B. one-to-many

                               C. many-to-many                                            C. strong

24.         Which of the following is true about supertype, subtype structure?

                               A. Relationship at the supertype level indicate that all subtypes will participate in the relationship

                               B. Subtype entities inherit values of all attribute of the supertype

                               C. An instance of a subtype is also an instance of the supertype

                               D. all of the above

25.         In the figure below, what is true about the attributes ItemNo and ComponentNo?

                               A. ItemNo in ITEM relation is a foreign key

                               B. ComponentNo has the same domain as ItemNo in ITEM relation

                               C. ItemNo in COMPONENT relation is a single primary key

                               D. none of the above

26.         The attribute on the left-hand side of the arrow in a functional dependency is a

                               A. primary key                                                  B. determinant

                               B. non-key                                                         C. none of the above

27.         A functional dependency of the form Student# à Advisor à Advisor_Office is called a:

                               A. partial functional dependency

                               B. partial non-key dependency

                               C. transitive dependency

                               D. partial transitive dependency

28.         Table 1 has a composite primary key (Order_No, Line_No) and the following two functional depencencies:

·        (Order_No, Line_No)à Item_No, Item_Description, Price, Quantity

·        Item_No à Item_Description, Price

               Table 1 is in:

                               A. 1NF                                                                  B. 2NF

                               C. 3NF                                                                  D. none of the above

29.         Which of the following is true about Table 1 of the above question?

                               A. Order_No alone can uniquely identify Item_No, Item_Description, Price, and Quantity

                               B. Item_No cannot uniquely identify Item_Description, and Price

                               C. Order_No and Line_No together can uniquely identify Item_No, Item Description, Price, and Quantity

                               D. All of the above

30.         The ________ rule specifies that an entity instance of a supertype is allowed not to belong to any subtype

                               A. Overlap                                                                          B. Disjoint

                               C. Total specialization                                                    D. Partial specialization