6th Edition 1 Optimizing Rdbms-Based Object Storage Tegarden

Appendix 9-1 Optimizing RDBMS-Based Object Storage
Testbank

Multiple Choices

1. A(n) _____ occurs when data are stored redundantly in a database and only some of the instances are updated when a change is needed.

a. error

b. update anomaly

c. data integrity concern

d. storage efficiency

e. none of these

1. A data model that does not contain repeating fields and that the data models leads to tables containing fields that are dependent on a whole primary key is in _____ normal form.

a. balanced

b. first

c. primary

d. second

e. third

1. If the data model does not have any repeating fields it is in _____.

a. base normal form

b. first normal form

c. non-normal form

d. second normal form

e. third normal form

1. If the logical data model contains fields that depend on another non-primary key field, then it is in violation of the rules of _____.

a. base normal form

b. first normal form

c. non-normal form

d. second normal form

e. third normal form

1. In order to reduce the number of joins that must be performed in a query and to increase the speed of data access, the data analyst will _____ the physical model.

a. cluster

b. denormalize

c. index

d. normalize

e. optimize

1. To improve the access speed of a database, similar records in a table are stored together in primary key order. This optimizing access speed process is called _____.

a. denormalization

b. indexing

c. interfile clustering

d. intrafile clustering

e. volumetrics

1. _____ is the process of estimating the amount of data that the hardware will need to support, so that the server hardware specifications are sufficient for the project’s needs.

a. Indexing

b. Interfile clustering

c. Intrafile clustering

d. Raw data calculating

e. Volumetrics

1. The size of a database is determined by the _____.

a. amount of raw data in the tables

b. amount of raw data in the tables and overhead requirements for the DBMS

c. number of instances in the tables

d. overhead requirements for the DBMS

e. overhead requirements for the DBMS and number of instances in the tables

1. A mini-table that contains values from one or more columns in a table and the location of the values within the table is called a(n) _____.

a. index

b. interfile cluster

c. intrafile cluster

d. raw data calculation

e. volumetric

1. A simple rule to follow when creating problem domain classes and data access and manipulation classes is that there should be ______________.

a. One data access and manipulation class for each concrete problem domain class

b. Two data access and manipulation classes for each concrete problem domain class

c. N data access and manipulation classes for each concrete problem domain class, where N is the number of methods in the problem domain class

d. N data access and manipulation classes for each concrete problem domain class, where N is the number of subclasses of the problem domain class

e. none of these

True/False

1. Normalization is a process that applies a series of rules to a logical data model to determine how well the model is formed.
2. Denormalization of a data model reduces the number of joins that must be performed in a query, which increases the speed of data access.
3. There are several techniques that the project team can use to try to speed up access to the data: denormalization, clustering, and indexing.
4. Null values in a database are easy to interpret.
5. Clustering similar records together is one way of reducing access time.
6. Information in a file's records that specifies the location of related records is called a marker.
7. The normalization process is performed primarily to increase the database's storage efficiency.
8. The most efficient tables in a relational database in terms of storage space have redundant data and few null values.
9. When the analyst is evaluating a data model to ensure that all fields in a record depend fully on the entire primary key, the analyst is making sure that the data model conforms to the second normal form.
10. A method for improving data access that involves physically arranging the records on the storage medium is called clustering.
11. The process of adding redundancy back into a physical data model is known as denormalization.
12. Denormalization is performed before the object storage is optimized.

Short Answer

1. Explain the term denormalization.
2. Explain the term clustering.
3. Explain the term Indexing.
4. Explain the term Volumetrics.
5. Summarize the first three steps of the normalization process.
6. Discuss the three situations in which denormalization will reduce joins and improve data access performance.
7. Why would an analyst both normalize and denormalize the design of the data management layer?