Chapter 8: Data Structures and CAATTs for Data Extraction

Question 1

Data structures have two fundamental components:

Answer 1

organization and access method

Question 2

_______________ refers to the way records are physically arranged on the secondary storage device. This may be either sequential or random.

Answer 2

Organization

Question 3

The _______________ is the technique used to locate records and to navigate through the database or
file.

Answer 3

access method

Question 4

Under this arrangement, for example, the record with key value 1875 is placed in the physical storage space immediately following the record with key value 1874. Thus, all records in the file lie in contiguous storage spaces in a specified sequence (ascending or descending) arranged by their primary key.

Answer 4

sequential structure

Question 5

An ________________ is so named because, in addition to the actual data file, there exists a separate index that is itself a file of record addresses. This index contains the numeric
value of the physical disk storage location (cylinder, surface, and record block) for each record in the associated data file.

Answer 5

indexed structure

Question 6

Records in an _________________ are dispersed throughout a disk without regard for their physical proximity to other related records

Answer 6

indexed random file

Question 7

The ___________________________structure is used for very large files that require routine batch processing and a moderate degree of individual record processing. For instance, the customer file of a public utility company will be processed in batch mode for billing purposes and directly accessed in response to individual customer
queries

Answer 7

Virtual Storage access method (VSAM)

Question 8

A VSAM file has three physical components:

Answer 8

the indexes
the prime data storage area
the overflow area.

Question 9

A ______________ employs an algorithm that converts the primary key of a record directly into a storage address.

Answer 9

hashing structure

Question 10

The principal advantage of hashing is _____________________.

Answer 10

access speed

Question 11

________________ is used to create a linked-list file.

Answer 11

pointer structure

Question 12

A ___________________ contains the actual disk
storage location (cylinder, surface, and record number) needed by the disk controller. This physical address allows the system to access the record directly without obtaining
further information. This method has the advantage of speed, since it does not need to be manipulated further to determine a record’s location.

Answer 12

physical address pointer

Question 13

A _____________ contains the relative position of a record in the file. For
example, the pointer could specify the 135th record in the file. This must be further manipulated to convert it to the actual physical address. The conversion software calculates this by using the physical address of the beginning of the file, the length of each record
in the file, and the relative address of the record being sought.

Answer 13

relative address pointer

Question 14

A _________________ contains the primary key of the related record. This key value is then converted into the record’s physical address by a hashing algorithm.

Answer 14

logical key pointer

Question 15

This structure uses an index in conjunction with a sequential file organization. It facilitates both direct access to individual records and batch processing of the entire file. Multiple indexes can be used to create a cross-reference, called an inverted list, which allows even more flexible access to data.

Answer 15

indexed sequential file structure

Question 16

An _______ is anything about which the organization wishes to capture data. These may be physical, such as inventories, customers, or employees. They may also be conceptual, such as sales (to a customer), accounts receivable (AR), or accounts payable (AP).

Answer 16

entity

Question 17

The term _____________ is used to describe the number of instances or records that pertain to a specific entity.

Answer 17

occurrence

Question 18

______________ are the data elements that define an entity.

Answer 18

Attributes

Question 19

The labeled line connecting two entities in a data model describes the nature of the
___________ between them.

Answer 19

association

Question 20

_____________ is the degree of association between two entities

Answer 20

Cardinality

Question 21

__________ describes the number of possible occurrences in one table that are associated with a single occurrence in a related table.

Answer 21

cardinality

Question 22

Four basic forms of cardinality are
possible:

Answer 22

zero or one (0,1)
one and only one (1,1)
zero or many (0,M)
one or many (1,M).

Question 23

The value of at least one attribute in each occurrence (row) must be unique. This attribute is the ______________________.

Answer 23

primary key

Question 24

Logically related tables need to be physically connected to achieve the associations described in the data model using _________________.

Answer 24

foreign keys

Question 25

A ____________ is the set of data that a particular user sees. Examples of this are computer screens for entering or viewing data, management reports, or source documents such as an invoice.

Answer 25

user view

Question 26

Improperly normalized tables can cause DBMS processing problems that restrict, or even deny, users access to the information they
need. Such tables exhibit negative operational symptoms called _________________.

Answer 26

anomalies

Question 27

To be free of anomalies, tables must be normalized to the _______________________.

Answer 27

third normal form (3NF) level.

Question 28

The _____________ results from data redundancy in an unnormalized table.

Answer 28

update anomaly

Question 29

The _______________ involves the unintentional deletion of data
from a table.

Answer 29

deletion anomaly

Question 30

_________________ is a component of a much larger systems development process that involves extensive analysis of user needs.

Answer 30

Database design

Question 31

Combining the data needs of all users into a single schema or enterprise-wide view is called _____________________.

Answer 31

view integration

Question 32

The objective of the ____________________, also known as continuous auditing, is to identify important transactions while they are being processed and extract copies of them in real time.

Answer 32

embedded audit module (EAM),

Question 33

An ____________ is a specially programmed module embedded in a host application to capture predetermined transaction types for subsequent analysis.

Answer 33

embedded audit module (EAM)

Question 34

Disadvantages of EAMs

Answer 34

1. Operational Efficiency - EAMs decrease operational performance
2. Verifying EAM Integrity - EAM may not be a viable audit technique in environments with a high level of program maintenance

Question 35

___________________ is the most widely used CAATT for IS auditing. It allows auditors to access electronically coded data files and perform various operations
on their contents.

Answer 35

Generalized audit software (GAS)

Question 36

The widespread popularity of GAS is due to four factors:

Answer 36

(1) GAS languages are easy to use and require little computer background on the part of the auditor;
(2) many GAS products can be used on both mainframe and PC systems;
(3) auditors can perform their tests independent of the client’s computer service staff; and
(4) GAS can be used to audit the data stored in most file structures and formats.

Question 37

_______________________ was designed as a meta-language for auditors to access data stored in various digital formats and to test them comprehensively.

Answer 37

ACL (audit command language)

Question 38

One of ACL’s strengths is the ability to read data stored in most formats.
ACL uses the __________________ for this purpose

Answer 38

data definition feature

Question 39

______________ are expressions that search for records that meet the filter criteria.

Answer 39

Filters

Question 40

________________________ allows the auditor to use logical operators such as AND, OR, , , NOT and others to define and test conditions of any complexity and to process only those records that match specific conditions

Answer 40

ACL’s expression builder

Question 41

_____________________________ feature allows the auditor to view the distribution of records that fall into specified strata.

Answer 41

ACL’s stratification

Question 42

Data can be stratified on any numeric field such as sales price, unitcost, quantity sold, and so on. The data are summarized and classified by strata, which can be equal in size (called ___________) or vary in size (called ___________).

Answer 42

intervals, free

Question 43

ACL offers many sampling methods for statistical analysis. Two of the most frequently used are ________________________.

Answer 43

record sampling and monetary unit sampling (MUS).