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 constraint? How does the referential integrity constraint contribute to database integrity?
3.45 Explain the role of referential integrity constraints in normalization.
3.46 Do relations StudID_SocialSecurityNumber and SocialSecurityNumber_StudName contain a transitive dependency?
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) S ActivityFee more accurate than Activity S 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 S S Sibling Name S ShoeSize Describe deletion, modification, and insertion anomalies for this relation.
3.53 Why is BCNF referred to as the best of the forms?
3.54 Consider the relation: PERSON_2 (Name, Sibling, ShoeSize, Hobby) Assume that the following functional dependencies exist: Name S S Sibling Name S ShoeSize Name S S Hobby Describe deletion, modification, and insertion anomalies for this relation.
3.55 What must we know in order to find functional dependencies in a table?
3.56 What is a multivalued dependency?
3.57 How do the conditions for DK/NF correspond to the conditions for BCNF