three.44 What is a referential integrity constraint? Define the time period, and give an instance of its use. Are null values allowed in overseas key columns with a referential integrity constraint? How does the referential integrity constraint contribute to database integrity?
three.45 Clarify the position of referential integrity constraints in normalization.
three.46 Do relations StudID_SocialSecurityNumber and SocialSecurityNumber_StudName include a transitive dependency?
three.47 In normalization instance three, why is the EXTENDED_PRICE relation “foolish”?
three.48 In normalization instance four, underneath what situations is the purposeful dependency (StudentID, Exercise) S ActivityFee extra correct than Exercise S ActivityFee
three.49 If a determinant is a part of a candidate key, is that adequate for BCNF?
three.50 In normalization instance 5, why are the following two tables not right? DEPARTMENT (Division, DeptBudgetCode, Purchaser) SKU_DATA_4 (SKU, SKU_Description, Division)
three.51 How does a multivalued dependency differ from a purposeful dependency?
three.52 Think about the relation: PERSON (Identify, Sibling, ShoeSize) Assume that the following purposeful dependencies exist: Identify S S Sibling Identify S ShoeSize Describe deletion, modification, and insertion anomalies for this relation.
three.53 Why is BCNF known as the better of the varieties?
three.54 Think about the relation: PERSON_2 (Identify, Sibling, ShoeSize, Interest) Assume that the following purposeful dependencies exist: Identify S S Sibling Identify S ShoeSize Identify S S Interest Describe deletion, modification, and insertion anomalies for this relation.
three.55 What should we all know with a view to discover purposeful dependencies in a desk?
three.56 What is a multivalued dependency?
three.57 How do the situations for DK/NF correspond to the situations for BCNF
