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1. In the Entity-Relationship model, the degree of a relationship specifies which of the following? (a) The cardinality ratio of the relationship (b) The number of integrity constraints required to implement the relationship (c) The number of attributes that characterize the relationship (d) The number of entities that participate in the relationship Correct answer is (d) - 2. In an ER model, which of the following is true about a component attribute? (a) A component attribute is always atomic. (b) Component attributes must always be combined by an aggregation operation. (c) A component attribute can be a composite attribute. (d) A component attribute always contains other components. Correct answer is (c) - 3. In the Entity-Relationship model, properties that characterize entities and relationships are modeled as (a) attributes (b) participation constraints (c) entity types (d) weak entities Correct answer is (a) - 4. What is an identifying owner in an ER model? (a) The entity upon which a weak entitys existence depends (b) The relationship that identifies a weak entitys owner (c) The entity upon which a strong entitys existence depends (d) The relationship that identifies a strong entitys owner Correct answer is (a) - 5. In an ER model, the cardinality ratio of a relationship type is (a) the number of instances of relationships of that relationship type (b) the number of entity types involved in that relationship type (c) the number of relationships of that relationship type in which an entity can participate (d) the minimum number of entities that can participate in that relationship type Correct answer is (c) 6. Which of the following is true about storage for derived attributes? (a) Derived attributes must not be stored. (b) Derived attributes are usually stored because storage improves retrieval performance. (c) Derived attributes must be stored. (d) Derived attributes are usually not stored because they can be computed. Correct answer is (d) - 7. In an ER model, what is a recursive relationship type? (a) A never-ending type of relationship (b) The type of relationship that does not belong anywhere (c) The type of relationship between entities of one entity type (d) The relationship type where the related entities are one and the same Correct answer is (c) -8. In EER modeling, generalization is the process of generating (a) superclasses out of subclasses (b) subclasses out of superclasses (c) entities out of attributes (d) attributes out of entities Correct answer is (a) -9. When mapping from an ER model to a relational model, a strong entity is mapped into a (a) table (b) row (c) column (d) key Correct answer is (a) -10. Which of the following is true about attributes in a relational model? Attributes can be multi-valued. Attributes can be composite. (a) Both I and II (b) II only (c) Neither I nor II (d) I only Correct answer is (c) 1. In an ER model, what is a recursive relationship type? (a) The relationship type where the related entities are one and the same (b) The type of relationship that does not belong anywhere (c) The type of relationship between entities of one entity type (d) A never-ending type of relationship Correct answer is (c) - 2. In an ER model, the cardinality ratio of a relationship type is (a) the number of relationships of that relationship type in which an entity can participate (b) the minimum number of entities that can participate in that relationship type (c) the number of entity types involved in that relationship type (d) the number of instances of relationships of that relationship type Correct answer is (a) - 3. In the Entity-Relationship model, a derived attribute is one (a) that is composed of multiple atomic attributes (b) that characterizes a relationship instead of an entity (c) that may have multiple values simultaneously (d) whose value can be computed from the values of other attributes Correct answer is (d) -4. In the Entity-Relationship model, properties that characterize entities and relationships are modeled as (a) entity types (b) weak entities (c) attributes (d) participation constraints Correct answer is (c) -5. Which of the following is true about storage for derived attributes? (a) Derived attributes must be stored. (b) Derived attributes are usually stored because storage improves retrieval performance. (c) Derived attributes must not be stored. (d) Derived attributes are usually not stored because they can be computed. Correct answer is (d) 6. What is an identifying owner in an ER model? (a) The relationship that identifies a weak entitys owner (b) The relationship that identifies a strong entitys owner (c) The entity upon which a strong entitys existence depends (d) The entity upon which a weak entitys existence depends Correct answer is (d) -7. In an ER model, which of the following is true about a component attribute? (a) A component attribute always contains other components. (b) A component attribute can be a composite attribute. (c) A component attribute is always atomic. (d) Component attributes must always be combined by an aggregation operation. Correct answer is (b) -8. In EER modeling, generalization is the process of generating (a) attributes out of entities (b) superclasses out of subclasses (c) subclasses out of superclasses (d) entities out of attributes Correct answer is (b) -9. When mapping from an ER model to a relational model, a strong entity is mapped into a (a) key (b) row (c) column (d) table Correct answer is (d) -10. Which of the following is true about attributes in a relational model? Attributes can be multi-valued. Attributes can be composite. (a) I only (b) II only (c) Neither I nor II (d) Both I and II Correct answer is (c) 1. Through normalization, update anomalies (a) can be eliminated (b) is usually left unchanged (c) can be maximized (d) can be minimized but not eliminated Correct answer is (a) -2. Which of the following is a property (are properties) exhibited by good relational schemas?The use of null values in tuples The grouping of as many attributes as possible into one main table The elimination of data redundancy to avoid update anomalies (a) III only (b) None (c) I and II only (d) II and III only Correct answer is (a) -3. Which of the following statements concerning normal forms is true? (a) A relation that is in second normal form is also in first normal form. (b) The lower the normal form number, the better the schema design is. (c) Each normal form contains a state of independent properties, unrelated to other normal forms. (d) Schemas that are in second normal form are considered the best. Correct answer is (a) -4. Consider the following functional dependency.A, B - CRegarding this dependency, which of the following statements is (are) true?The values of C are uniquely determined by the values of A. The values of A are uniquely determined by the values of C. (a) None (b) II only (c) I only (d) I and II Correct answer is (a) 5. Which of the following problems can be caused by data redundancy in a relational schema?Inefficient use of space Update anomalies and possible loss of data Inefficient use of processing time (a) I and II only (b) I and III only (c) I, II, and III (d) II only Correct answer is (c) -6. Consider a table with atomic attributes A, B, and C and the following functional dependencies.A - B B - CIf the primary key of this table is attribute A, then this relation satisfies which of the following normal forms?First Second Third (a) None (b) I only (c) I, II and III (d) I and II only Correct answer is (d) -7. For a relation to be in 3NF, it should not contain _ attribute that is transitively dependent on _. (a) a non-primary key, a foreign key (b) a primary key, a non-primary key (c) a primary key, a foreign key (d) a non-primary key, the primary key Correct answer is (d) -8. The FD X - Y is a full dependency in a relation R, if there is _ attribute A that can be _ X and the dependency still holds. (a) no, added to (b) no, removed from (c) at least one, removed from (d) at least one, added to Correct answer is (b) -9. For a relation to be in 2NF, _ attribute must be fully functionally dependent on _. (a) every non-primary-key, the primary key (b) every alternate key, the primary key (c) every non-key, every key (d) every non-key, at least one key Correct answer is (a) -10. The FD X - Y is a partial dependency in a relation R, if there is _ attribute A that can be _ X and the dependency still holds. (a) at least one, removed from (b) at least one, added to (c) no, added to (d) no, removed from Correct answer is (a) 1. Through normalization, update anomalies (a) can be eliminated (b) is usually left unchanged (c) can be minimized but not eliminated (d) can be maximized Correct answer is (a) -2. Consider the following functional dependency.A, B - CRegarding this dependency, which of the following statements is (are) true?The values of C are uniquely determined by the values of A. The values of A are uniquely determined by the values of C. (a) None (b) I and II (c) I only (d) II only Correct answer is (a) -3. Which of the following is a property (are properties) exhibited by good relational schemas?The use of null values in tuples The grouping of as many attributes as possible into one main table The elimination of data redundancy to avoid update anomalies (a) III only (b) None (c) II and III only (d) I and II only Correct answer is (a) -4. Through normalization, data redundancy (a) can be eliminated (b) can be maximized (c) can be minimized but not eliminated (d) are usually left unchanged Correct answer is (a) 5. Which of the following statements concerning normal forms is true? (a) A relation that is in second normal form is also in first normal form. (b) Each normal form contains a state of independent properties, unrelated to other normal forms. (c) Schemas that are in second normal form are considered the best. (d) The lower the normal form number, the better the schema design is. Correct answer is (a) -6. For a relation to be in 3NF, it should not contain _ attribute that is transitively dependent on _. (a) a primary key, a foreign key (b) a primary key, a non-primary key (c) a non-primary key, a foreign key (d) a non-primary key, the primary key Correct answer is (d) -7. The FD X - Y is a full dependency in a relation R, if there is _ attribute A that can be _ X and the dependency still holds. (a) no, removed from (b) at least one, removed from (c) at least one, added to (d) no, added to Correct answer is (a) -8. Consider a table with atomic attributes A, B, and C and the following functional dependencies.A - B B - CIf the primary key of this table is attribute A, then this relation satisfies which of the following normal forms?First Second Third (a) I, II and III (b) None (c) I and II only (d) I only Correct answer is (c) - 9. For a relation to be in 2NF, _ attribute must be fully functionally dependent on _. (a) every alternate key, the primary key (b) every non-key, at least one key (c) every non-key, every key (d) every non-primary-key, the primary key Correct answer is (d) -10. The FD X - Y is a partial dependency in a relation R, if there is _ attribute A that can be _ X and the dependency still holds. (a) no, added to (b) no, removed from (c) at least one, added to (d) at least one, removed from Correct answer is (d) 1. What is an identifying owner in an ER model? (a) The entity upon which a weak entitys existence depends (b) The relationship that identifies a weak entitys owner (c) The relationship that identifies a strong entitys owner (d) The entity upon which a strong entitys existence depends Correct answer is (a) -2. In an ER model, the cardinality ratio of a relationship type is (a) the minimum number of entities that can participate in that relationship type (b) the number of instances of relationships of that relationship type (c) the number of entity types involved in that relationship type (d) the number of relationships of that relationship type in which an entity can participate Correct answer is (d) -3. In the Entity-Relationship model, properties that characterize entities and relationships are modeled as (a) entity types (b) participation constraints (c) weak entities (d) attributes Correct answer is (d) -4. In an ER model, what is a recursive relationship type? (a) A never-ending type of relationship (b) The relationship type where the related entities are one and the same (c) The type of relationship between entities of one entity type (d) The type of relationship that does not belong anywhere Correct answer is (c) -5. In the Entity-Relationship model, a derived attribute is one (a) that characterizes a relationship instead of an entity (b) that may have multiple values simultaneously (c) whose value can be computed from the values of other attributes (d) that is composed of multiple atomic attributes Correct answer is (c) -6. In the Entity-Relationship model, the degree of a relationship specifies which of the following? (a) The number of attributes that characterize the relationship (b) The number of entities that participate in the relationship (c) The cardinality ratio of the relationship (d) The number of integrity constraints required to implement the relationship Correct answer is (b) -7. Which of the following is true about storage for derived attributes? (a) Derived attributes are usually not stored because they can be computed. (b) Derived attributes are usually stored because storage improves retrieval performance. (c) Derived attributes must be stored. (d) Derived attributes must not be stored. Correct answer is (a) -8. In EER modeling, generalization is the process of generating (a) superclasses out of subclasses (b) entities out of attributes (c) subclasses out of superclasses (d) attributes out of entities Correct answer is (a) -9. When mapping from an ER model to a relational model, a strong entity is mapped into a (a) key (b) table (c) row (d) column Correct answer is (b) -10. Which of the following is true about attributes in a relational model? Attributes can be multi-valued. Attributes can be composite. (a) II only (b) I only (c) Both I and II (d) Neither I nor II Correct answer is (d) 1. Which of the following is true about storage for derived attributes? (a) Derived attributes are usually stored because storage improves retrieval performance. (b) Derived attributes must be stored. (c) Derived attributes are usually not stored because they can be computed. (d) Derived attributes must not be stored. Correct answer is (c) -2. In an ER model, the cardinality ratio of a relationship type is (a) the minimum number of entities that can participate in that relationship type (b) the number of entity types involved in that relationship type (c) the number of relationships of that relationship type in which an entity can participate (d) the number of instances of relationships of that relationship type Correct answer is (c) -3. In the Entity-Relationship model, the degree of a relationship specifies which of the following? (a) The number of attributes that characterize the relationship (b) Th
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