3.2 What is the basic premise of this and the next chapter? 3.3 Explain what is wrong with the table in Figure 3-2. 3.4 Define each of the terms listed in Figure 3-3.
3.5 Describe the characteristics of a table that make it a relation. Define the term domain
and explain the significance of the domain integrity constraint to a relation.
3.6 Give an example of two tables that are not relations.
3.7 Suppose that two columns in two different tables have the same column name. What
convention is used to give each a unique name?
3.8 Must all the values in the same column of a relation have the same length?
3.9 Explain the three different sets of terms used to describe tables, columns, and rows. 3.10 Explain the difference between functional dependencies that arise from equations and
those that do not.
3.11 Explain the intuitive meaning of the functional dependency.
PartNumber→ PartWeight
3.12 Explain the following statement: “The only reason for having relations is to store instances of
functional dependencies.”
3.13 Explain the meaning of the expression:
(FirstName, LastName) →Phone
3.14 What is a composite determinant?
3.15 If (A, B) →C , then can we also say that A→ C? 3.16 If A →(B, C), then can we also say that A → B?
3.17 For the SKU_DATA table in Figure 3-1, explain why Buyer determines Department, but
Department does not determine Buyer.
3.18 For the SKU_DATA table in Figure 3-1, explain why:
SKU_Description→(SKU, Department, Buyer).
3.19 If it is true that
PartNumber S PartWeight
does that mean that PartNumber will be unique in a relation?
3.20 Under what conditions will a determinant be unique in a relation? 3.21 What is the best test for determining whether a determinant is unique? 3.22 What is a composite key? 3.23 What is a candidate key?
3.24 What is a primary key? Explain the significance of the entity integrity constraint to a
primary key.
3.25 Explain the difference between a candidate key and a primary key. 3.26 What is a surrogate key?
3.27 Where does the value of a surrogate key come from? 3.28 When would you use a surrogate key?
3.29 What is a foreign key? Explain the significance of the referential integrity constraint to a
foreign primary key.
3.30 The term domestic key is not used. If it were used, however, what do you think it would
mean?
3.31 What is a normal form?
3.32 Illustrate deletion, modification, and insertion anomalies on the STUDENT_ACTIVITY
relation in Figure 3-24.
3.33 Explain why duplicated data lead to data integrity problems. 3.34 What relations are in 1NF?
3.35 Which normal forms are concerned with functional dependencies? 3.36 What conditions are required for a relation to be in 2NF? 3.37 What conditions are required for a relation to be in 3NF? 3.38 What conditions are required for a relation to be in BCNF?
3.39 If a relation is in BCNF, what can we say about it with regard to 2NF and 3NF? 3.40 What normal form is concerned with multivalued dependencies? 3.41 What is the premise of Fagin’s work on DK/NF? 3.42 Summarize the three categories of normalization theory.
3.43 In general, how can you transform a relation not in BCNF into ones that are in
BCNF?
3.44 What is a referential integrity constraint? Define the term, and give an example of
its use. Are null values allowed in foreign key columns with a referential integrity constrain? How does the referential integrity constrain contribute to database integrity?
3.45 Explain the role of referential integrity constraints in normalization. 3.46 Why is an un-normalized relation like a paragraph with multiple themes? 3.47 In normalization example 3, why is the EXTENDED_PRICE relation “silly”? 3.48 In normalization example 4, under what conditions is the functional dependency
(StudentID, Activity) → ActivityFee more accurate than Activity→ ActivityFee
3.49 If a determinant is part of a candidate key, is that good enough for BCNF? 3.50 In normalization example 5, why are the following two tables not correct?
DEPARTMENT (Department, DeptBudgetCode, Buyer) SKU_DATA_4 (SKU, SKU_Description, Department)
3.51 How does a multivalued dependency differ from a functional dependency? 3.52 Consider the relation:
PERSON (Name, Sibling, ShoeSize)
Assume that the following functional dependencies exist: Name →→Sibling Name → ShoeSize
Describe deletion, modification, and insertion anomalies for this relation.
3.53 Place the PERSON relation in Review Question 3.52 into 4NF. 3.54 Consider the relation:
PERSON_2 (Name, Sibling, ShoeSize, Hobby) Assume that the following functional dependencies exist: Name →→Sibling Name → ShoeSize Name →→Hobby
Describe deletion, modification, and insertion anomalies for this relation.
3.55 Place the PERSON_2 relation in Review Question 3.54 into 4NF. 3.56 What is 5NF?
3.57 How do the conditions for DK/NF correspond to the conditions for BCNF?
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