65 terms

My System Analysis Ch.5

STUDY
PLAY

Terms in this set (...)

In a DFD, a process symbol can have only one outgoing data flow.
False
Leveling also is called ____.
exploding
partitioning
decomposing
Many valuable reports can be obtained from a data dictionary, including a(n) ____.
alphabetized list of all data elements by name

report by user departments of data elements that must be updated by each department

report of all data flows that use a particular data element
detailed report showing all characteristics of data elements
Typical process description tools include ____.
decision trees
In modular design, each logical structure must have multiple entry and exit points.
False
In a data dictionary, some data elements have ____ rules, such as an employee's salary must be within the range defined for the employee's job classification.
validity
The primary purpose of pseudocode is to describe the underlying business logic of code
False
In addition to describing each data element, data flow, data store, record, entity, and process, the data dictionary documents the relationships among these components.
True
In modular design, a rectangle represents a condition or decision, a diamond shape represents a step or a process, and the logic follows the lines in the direction indicated by the arrows.
False
The disadvantage of the four-model approach is ____.
the added time and cost needed to develop a logical and physical model of the current system
A DFD shows the structure and detailed contents of a data flow.
False
A DFD shows ____.
how a system transforms input data into useful information
what data is stored in the system
A spontaneous generation process is a process that has ____.
no input
In a DFD, the Gane and Sarson symbol for an entity is a ____.
rectangle, which may be shaded to make it look three-dimensional
A disadvantage of the four-model approach is that the requirements of a new information system always are quite different from the current information system, especially when the proposal is based on new computer technology rather than a large number of new requirements.
False
A DFD does not show the external entities that provide data to the system or receive output from the system.
False
A decision ____ is a graphical representation of the conditions, actions, and rules found in a decision table
tree
In a DFD, a data flow must have a process symbol on at least one end.
True
The major benefit of ____ is that it gives a clear picture of current system functions before any modifications or improvements are made.
the four-model approach
In a DFD, the Gane and Sarson symbol for a data store is a ____.
flat rectangle that is open on the right side and closed on the left side
DFD symbols are referenced by using all ____ letters for the symbol name.
capital
In a DFD, the Gane and Sarson symbol for a process is a ____.
rectangle with rounded corners
A data ____ is a central storehouse of information about a system's data
repository
A gray hole is a process that has ____.
at least one input and one output, but the input obviously is insufficient to generate the output shown
Decision trees show the logic structure in a ____.
horizontal form that resembles a tree with the roots at the left and the branches to the right
Two DFDs are leveled, for example, if the child diagram at the bottom has the same input and output flows as the parent process at the top of the diagram.
False
The data dictionary usually records and describes a default value, which is the ____.
value for the data element if a value otherwise is not entered for it
Deciding whether to explode a process further or determine that it is a functional primitive is a matter of experience, judgment, and interaction with programmers who must translate the logical design into code
True
In a DFD, the Gane and Sarson symbol for a data flow is a ____.
line with a single or double arrowhead
Systems analysts call an entity that receives data from the system a source.
False
The selection structure is the completion of ____.
one or more process steps based on the results of a test or condition
What makes one system more complex than another is the number of components, the number of levels, and the degree of interaction among its processes, entities, data stores, and data flows.
True
A ____ description documents the details of a functional primitive, which represents a specific set of processing steps and business logic.
process
In a DFD, processes contain the business logic, also called business rules, that transform the data and produce the required results.
True
When a context diagram is expanded into DFD diagram 0, all the connections that flow into and out of process 0 must be retained.
True
More complex systems have fewer processes, and analysts need only work through very few levels to identify the functional primitives.
False
Deciding whether to explode a process further or determine that it is a functional primitive is a matter of experience, judgment, and interaction with programmers who must translate the logical design into code.
True
A black hole is a process that has ____.
no output
Systems analysts call an entity that supplies data to the system a sink.
False
Whether to use a decision table or a decision tree often is a matter of personal preference
True
Using Gane and Sarson symbols, a DFD represents processes as rectangles with rounded corners.
True
In the accompanying figure, the sequence structure is the completion of ____.
steps in a chronological order, one after another
When documenting a process, the documentation includes a description of the process's characteristics and, for functional primitives, a process description, which is a model that documents the processing steps and business logic.
True
DFDs are balanced if each internal process is numbered to show that it is a child of the parent process.
False
Data stores are shown in a context diagram because data stores are external to the system.
False
When structured English is used, which of the following rules must be conformed to?
use only the three building blocks of sequence, selection, and iteration

use indentation for readability
use a limited vocabulary
A ____ table shows a logical structure, with all possible combinations of conditions and resulting actions.
decision
____ is the process of drawing a series of increasingly detailed DFDs, until all functional primitives are identified.
Leveling
In a data dictionary, some data elements have ____ rules, such as an employee's salary must be within the range defined for the employee's job classification.
validity
In a data dictionary, ____ is the maximum number of characters for an alphabetic or character data element or the maximum number of digits and number of decimal positions for a numeric data element.
length
In most data dictionaries, records are defined together with the data flows and data stores.
False
In a data dictionary, ____ refers to whether the data element contains numeric, alphabetic, or character values.
type
Leveling ____.
uses a series of increasingly detailed DFDs to describe an information system
In a data dictionary, data elements are combined into ____, which are meaningful combinations of data elements that are included in data flows or retained in data stores.
records
When a DFD is exploded, the higher-level diagram is called the child diagram, and the lower-level diagram is referred to as the parent diagram.
False
When you explode a DFD, the higher-level diagram is called the ____ diagram
parent
When DFDs are drawn, which of the following conventions should be followed?
each context diagram must fit on one page
Correct do not cross lines
Correct use a unique reference number for each process symbol
____ is/are logically impossible in a DFD because a process must act on input, shown by an incoming data flow, and produce output, represented by an outgoing data flow.
Black holes
When documenting a process, the documentation includes a description of the process's characteristics and, for functional primitives, a process description, which is a model that documents the processing steps and business logic.
True
A decision ____ is a graphical representation of the conditions, actions, and rules found in a decision table.
tree
Later in the systems design phase, you build a logical model that describes how a system will be constructed.
False
____ maintains consistency among DFDs by ensuring that input and output data flows align properly.
Balancing
The primary purpose of pseudocode is to describe the underlying business logic of code.
False
A decision tree is read from left to right, with the conditions along the various branches and the actions at the far left.
False
When drawing DFDs, a data store is shown only when two or more processes use that data store.
True