Q&A Hero

Q: When a table contains only one candidate key, ________________are considered to be equivalent.a. the 1NF and the 2NFb. the 3NF and the BCNFc. the 4NF and the 3NFd. the BCNF and the DKNF

Q: BCNF can be violated only if the table contains more than one ______________-key.a. primaryb. candidatec. foreignd. secondary

Q: In a______________ situation, one key determines multiple values of two other attributes and those attributes are independent of each other.a. multivalued dependencyb. transitive dependencyc. partial dependencyd. functional dependency

Q: A table where every determinant is a candidate key is said to be in___________ .a. BCNFb. 2NFc. 1NFd. 4NF

Q: To generate a surrogate key, Microsoft Access uses a(n)_________ data type.a. characterb. sequencec. AutoNumberd. identity

Q: For most business transactional databases, we should normalize relations into_________-- .a. 1NFb. 2NFc. 3NFd. 6NF

Q: In a real-world environment, we must strike a balance between design integrity and______________ .a. robustnessb. flexibilityc. uniquenessd. ease of use

Q: From a system functionality point of view, __________attribute values can be calculated when they are needed to write reports or invoices.a. derivedb. atomicc. granulard. historical

Q: Granularity refers to__________ .a. the size of a tableb. the level of detail represented by the values in a table's rowc. the number of attributes represented in a tabled. the number of rows in a table

Q: The most likely data type for a surrogate key is__________ .a. characterb. datec. logicald. numeric

Q: An atomic attribute_______________ .a. cannot exist in a relational tableb. cannot be further subdividedc. displays multiplicityd. is always chosen to be a foreign key

Q: Improving__________ leads to more flexible queries.a. atomicityb. normalizationc. denormalizationd. derived attribute

Q: A table that is in 2NF and contains no transitive dependencies is said to be in_____________ .a. 1NFb. 2NFc. 3NFd. 4NF

Q: If a table has multiple candidate keys and one of those candidate keys is a composite key, the table can have___________based on this composite candidate key even when the primary key chosen is a single attribute.a. Boyce-Codd normal formsb. redundanciesc. time-variancesd. partial dependencies

Q: A(n)__________ exists when there are functional dependencies such that XY is functionally dependent on WZ, X is functionally dependent on W, and XY is the primary key.a. atomic attributeb. repeating groupc. partial dependencyd. transitive dependency

Q: Before converting a table into 3NF, it is imperative that the table already be in_________- .a. 1NFb. 2NFc. 4NFd. BCNF

Q: If you have three different transitive dependencies,___________ different determinant(s) exist.a. oneb. twoc. threed. four

Q: A table that is in 1NF and includes no partial dependencies is said to be in______________ .a. BCNFb. 2NFc. 3NFd. 4NF

Q: A table that has all key attributes defined, has no repeating groups, and all its attributes are dependent on the primary key is said to be in__________ .a. 1NFb. 2NFc. 3NFd. 4NF

Q: In a(n)__________ diagram, the arrows above the attributes indicate all desirable dependencies.a. Chenb. dependencyc. functionalityd. ER

Q: Dependencies based on only a part of a composite primary key are known as __________dependencies.a. primaryb. partialc. incompleted. composite

Q: A relational table must not contain a(n)______________ .a. entityb. attributec. relationshipd. repeating group

Q: A___________ derives its name from the fact that a collection of multiple entries of the same type can exist for any single key attribute occurrence.a. partial dependencyb. transitive dependencyc. repeating groupd. primary key

Q: Attribute A _______________attribute B if all of the rows in the table that agree in value for attribute A also agree in value for attributeB.a. determinesb. derives fromc. controlsd. owns

Q: A(n)___________ exists when there are functional dependencies such that Y is functionally dependent on X, Z is functionally dependent on Y, and X is the primary key.a. partial dependencyb. repeating groupc. atomic attributed. transitive dependency

Q: Of the following normal forms,_________ is mostly of theoretical interest.a. 1NFb. 3NFc. BCNFd. DKNF

Q: Some very specialized applications may require normalization beyond the_______________ .a. 1NFb. 2NFc. 3NFd. 4NF

Q: Data redundancy produces_________ .a. slower lookupsb. robust designc. efficient storage used. data integrity problems

Q: A table that displays data redundancies yields___________- .a. consistenciesb. anomaliesc. fewer attributesd. more entities

Q: An attribute that is part of a key is known as a(n)__________ attribute.a. importantb. nonprimec. primed. entity

Q: ____________yields better performance.a. Denormalizationb. Normalizationc. Atomizationd. Compression

Q: From a structural point of view, 2NF is better than___________ .a. 1NFb. 3NFc. 4NFd. BCNF

Q: 1NF, 2NF, and 3NF are_____________ .a. normalization stagesb. anomaliesc. repeating groupsd. atomic attributes

Q: From a structural point of view, 3NF is better than____________ .a. 4NFb. 2NFc. 5NFd. 6NF

Q: Normalization works through a series of stages called normal forms. For most purposes in business database design,_______ stages are as high as you need to go in the normalization process.a. twob. threec. fourd. five

Q: Attributes should clearly define participation, connectivity, and document cardinality.a. Trueb. False

Q: Unnormalized database tables often lead to various data redundancy disasters in production databases.a. Trueb. False

Q: Normalization purity is often easy to sustain in the modern database environment.a. Trueb. False

Q: The advantage of higher processing speed must be carefully weighed against the disadvantage of data anomalies.a. Trueb. False

Q: A good relational DBMS excels at managing denormalized relations.a. Trueb. False

Q: The combination of normalization and ER modeling yields a useful ERD, whose entities can be translated into appropriate relationship structures.a. Trueb. False

Q: Normalization represents a micro view of the entities within the ERD.a. Trueb. False

Q: Normalization should be part of the design process. a. True b. False

Q: Atomic attributes are attributes that can be further subdivided.a. Trueb. False

Q: Data stored at their highest level of granularity are said to be atomic data. a. True b. False

Q: A dependency of one nonprime attribute on another nonprime attribute is a partial dependency. a. True b. False

Q: A determinant is any attribute whose value determines other values within a column. a. True b. False

Q: It is possible for a table in 2NF to exhibit transitive dependency, where the primary key may rely on one or more nonprime attributes to functionally determine other nonprime attributes. a. True b. False

Q: A table is in 2NF if it is in 1NF, and it includes no partial dependencies. a. True b. False

Q: Since a partial dependency can exist only if a table's primary key is composed of several attributes, if a table in 1NF has a single-attribute primary key, then the table is automatically in 2NF. a. True b. False

Q: Converting a database format from 1NF to 2NF is a complex process. a. True b. False

Q: In the context of partial dependencies, data redundancies occur because every row entry requires duplication of data. a. True b. False

Q: All relational tables satisfy the 1NF requirements. a. True b. False

Q: Dependencies that are based on only a part of a composite primary key are called transitive dependencies. a. True b. False

Q: Dependency diagrams are very helpful in getting a bird'seye view of all the relationships among a table's attributes.a. Trueb. False

Q: Repeating groups must be eliminated by ensuring that each row defines a single entity. a. True b. False

Q: The objective of normalization is to ensure that each table conforms to the concept of well-formed relations. a. True b. False

Q: Relational models view data as part of a table or collection of tables in which all key values must be identified.a. Trueb. False

Q: A table is in fourth normal form if it is in third normal form and has no independent multivalued dependencies. a. True b. False

Q: A dependency based on only a part of a composite primary key is known as a partial dependency. a. True b. False

Q: A table is in BCNF if every determinant in the table is a foreign key. a. True b. False

Q: A table is in BCNF if every determinant in the table is a candidate key. a. True b. False

Q: Data redundancy produces data anomalies. a. True b. False

Q: Reporting anomalies in a table can cause a multitude of problems for managers and can be fixed through application programming. a. True b. False

Q: Normalization is a very important database design ingredient, and the highest level is always the most desirable. a. True b. False

Q: Denormalization produces a lower normal form. a. True b. False

Q: In order to meet performance requirements, portions of the database design may need to be occasionally denormalized.a. Trueb. False

Q: Normalization is a process that is used for changing attributes to entities. a. True b. False

Q: Normalization produces a lower normal form. a. True b. False

Q: Normalization works through a series of stages called normal forms. a. True b. False

Q: In which two cases are composite primary keys particularly useful?

Q: Explain the "no change over time" characteristic of a primary key.

Q: Describe an entity cluster.

Q: Explain the two criteria that help a designer in determining when to use subtypes and supertypes.

Q: Differentiate between specialization and generalization.

Q: What do specialization hierarchies do?

Q: The main concern with redundant relationships is that they remain across________ the model.

Q: A___________ occurs when a relationship is improperly or incompletely identified and is therefore represented in a way that is not consistent with the real world.

Q: From a data modeling point of view, ___________--data refer to data whose values change over time and for which one must keep a history of the data changes.

Q: While using a surrogate key, one must ensure that the candidate key of the entity in question performs properly through the use of the "_________ " and "not null" constraints.