ISYS 330 Text 2 Quizlet
Data Store
data that are at rest in a system; depicted using an open-ended rectangle in data flow diagrams
In a decision table, contradictions occur when:
rules suggest different actions but satisfy the same conditions.
The data dictionary may be used to create:
screens, reports, and forms
Minispecs
see process specification
What is a way to examine, describe, and document structured decisions?
decision table
Decision table
A decision table is a table of rows and columns, separated into four quadrants.
Process logic may be represented as:
A) structured English. B) a decision table. C) a decision tree. D) a formula. E) All of the above. E is correct
Scrum
- Begin the project with a high-level plan that can be changed on the fly - Success of the project is most important - Individual success is secondary - Project leader has some (not much) influence on the detail - Systems team works within a strict time frame
________ are an important tool in the analysis of structured decisions.
- Decision tables
How can an event table be used to create a data flow diagram?
used to create a data flow diagram by analyzing each event and the data used and produced by the event, every row in an event table represents a unique activity and is used to create one process on the data flow diagram.
When are transaction files required in a system's design?
used to link any processes that do not execute at the same time but share the same data
Which of the following is not a business rule?
user ethics
A goal of producing process specifications is to:
validate the system design, including data flow diagrams and the data dictionary.
A data type of __________ is used for elements that can contain any number of characters up to the limit set by the database software.
varchar
Basic Principles of Agile Modeling
- Encourage continuous, regular, and sustainable development - Embrace change, even if introduced late in development - Provide rapid feedback - Encourage quality - Review and adjust behavior occasionally - Adopt simplicity - Continue to deliver functioning software incrementally and frequently
Comparing Agile Modeling and Structured Methods
- Improving the efficiency of systems development - Risks inherent in organizational innovation - Adopting New Information - Systems Involves Balancing - Several Risks
The Agile Development Process
- Listen for user stories - Draw a logical workflow model - Create new user stories based on the logical model - Develop some display prototypes - Create a physical data model using feedback from the prototypes and logical workflow diagrams
Lessons Learned from Agile Modeling:
- Short releases allow the system to evolve - Pair programming enhances the overall quality - Onsite customers are mutually beneficial to the business and the agile development team - The 40-hour work week improves worker effectiveness - Balanced resources and activities support project goals - Agile values are crucial to success
What are the four data items that can be symbolized on a data flow diagram?
1. A double square for an external entity—a source or destination of data 2. An arrow for movement of data from one point to another 3. A rectangle with rounded corners for the occurrence of transforming process 4. An open-ended rectangle for a data store
Four Basic Activities of Agile Modeling
1. Coding 2. Testing 3. Listening 4. Designing
Disadvantages of Prototyping
1. Difficult to manage prototyping as a project 2. Users and analysts may adopt a prototype as a completed system
What are the four advantages of using a data flow approach over narrative explanations of data movement?
1. Freedom from committing to the technical implementation of the system too early 2. Further understanding of the interrelationships of systems and subsystems 3. Communicating current system knowledge to users through data flow diagrams 4. Analysis of the proposed system to determine if all the data and processes have been defined
Advantages of Prototyping
1. Potential for changing the system early in it's development 2. Opportunity to stop development on a system that is not working 3. Possibility of developing a system that more closely addresses user's needs
Guidelines for Developing a Prototype
1. Work in manageable modules 2. Build the prototype rapidly to gain insight 3. Modify prototype in successive iterations 4. Stress the user interface
Agile Modeling
A collection of innovative, user centered approaches to system development
Data Flow Diagram (DFD)
A graphical depiction of data process, data flows, and data stores in a business system
List three reasons for creating a logical data flow diagram.
A logically-oriented data flow diagram should be created for the following reasons: 1. Better communication with users. 2. More stable systems. 3. Increased understanding of the business by analysts.
What is the difference between a logical data flow diagram and a physical data flow diagram?
A logically-oriented data flow diagram shows how the business operates. A physically-oriented data flow diagram shows how the system will be implemented using technology and manual procedures
Ajax
A method using JavaScript and XML to dynamically change Web pages without displaying a new page by obtaining small amounts of data from the server
First-of-a-series
A pilot prototype that is completely operational
Nonoperational
A scale model that is set up to test certain aspects of the design
Patched-up
A system that works but it patched up or patched together
A synonym or other name for an element is called a(n):
Alias
Selected Features
An operational model that includes some, but not all, of the features that the final system will have
4. What are the two building blocks of structured English?
As the name implies, structured English is based on (1) structured logic, or instructions organized into nested and grouped procedures, and (2) simple English statements such as add, multiply, and move.
What are characteristic of the ideal data dictionary?
Automated, interactive, online, evolutionary, and (NOT) efficient
In order to use structured English, which convention is not advisable?
Blank a line and indent blocks of statements to show their hierarchy
Process descriptions may exist on a form or within a ________ repository.
CASE tool
Values and Principles of Agile Modeling
Communication, simplicity, feedback, courage
15. In which two situations do decision tables work best?
Complex combinations of conditions, actions, and rules are found, You require a method that effectively avoids impossible situations, redundancies, and Contradictions
When creating process specifications, what needs to be done for manual tasks?
Create well-defined procedures for employees performing the tasks.
When iteration is indicated for an element or a group of elements in the data dictionary:
DO WHILE, DO UNTIL, or PERFORM UNTIL structured English statements must be included.
What is one of the main methods available for an analyst to use when analyzing data-oriented systems?
Data Flow Diagrams
__________ is usually the first component to be stored in the data dictionary.
Data flow
________ are used when complex branching occurs in a structured decision process.
Decision trees
11. What are the main uses of decision trees in systems analysis?
Decision trees are used when complex branching occurs in a structured decision process. Trees are also useful when it is essential to keep a string of decisions in a particular sequence.
In order to build decision tables, what does the analyst not need to do?
Determine the minimum size of the table.
8. What is the first step to take in developing a decision table?
Determine the number of conditions that may affect the decision. Combine rows that overlap, such as conditions that are mutually exclusive. The number of conditions becomes the number of rows in the top half of the decision table.
5. List five conventions that should be followed when using structured English.
Express all logic in terms of one of these four types: sequential structures, decision structures, case structures, or iterations Use and capitalize accepted keywords such as IF, THEN, ELSE, DO, DO WHILE, DO UNTIL, and PERFORM. Indent blocks of statements to show their hierarchy (nesting) clearly. When words or phrases have been defined in a data dictionary, underline those words or phrases to signify that they have a specialized, reserved meaning. Be careful when using "and" and "or," and avoid confusion when distinguishing between "greater than" and "greater than or equal to" and like relationships. "A and B" means both A and B; "A or B" means either A or B, but not both. Clarify the logical statements now rather than waiting until the program coding stage.
9. List the four main problems that can occur in developing decision tables?
Four main problems can occur in developing decision tables: incompleteness, impossible situations, contradictions, and redundancy.
A data structure with optional elements contained in parenthesis or either/or elements contained
IF ...THEN ...ELSE
Which of the following is not an example of a keyword for structured English?
IS LIKE
12. List the two major steps in building decision trees.
Identify all conditions and actions and their order and timing (if they are critical). Begin building the tree from left to right, making sure you list all possible alternatives before moving to the right.
3. What four elements must be known for the systems analyst to design systems for structured decisions?
It is important to be able to recognize logic and structured decisions that occur in a business and how they are distinguishable from semi-structured decisions that tend to involve human judgment. Then it is critical to recognize that structured decisions lend themselves particularly well to analysis with systematic methods that promote completeness, accuracy, and communication.
Braces { } are used to indicate:
Iteration
________, indicated by braces on a data structure, must have a corresponding DO WHILE, DO UNTIL, or PERFORM UNTIL structured English statement.
Iteration
In order to determine the human information requirements using a decision analysis strategy, what must the systems analyst determine?
Objectives
10. What is one of the major advantages of decision tables over other methods of decision analysis?
One major advantage of using decision tables over other methods is that tables help the analyst ensure completeness.
2. Define what is meant by a structured decision.
One way to describe structured decisions is to use the method referred to as structured English, in which logic is expressed in sequential structures, decision structures, case structures, or iterations.
Action
Organized activity to accomplish an objective
Unlike the decision tree used in management science, what doesn't the analyst's tree contain?
Outcomes
__________ data structures include additional elements necessary for implementing the system.
Physical
________ are created for primitive processes on a data flow diagram.
Process specifications
Scrum:
Product backlog, Sprint backlog, Daily scrum, Demo
Four Core Agile Practices
Short releases, 40-hour work week, onsite customer, pair programming
13. What three advantages do decision trees have over decision tables?
The decision tree has three main advantages over a decision table. First, it takes advantage of the sequential structure of decision tree branches so that the order of checking conditions and executing actions is immediately noticeable. Second, conditions and actions of decision trees are found on some branches but not on others, which contrasts with decision tables, in which they are all part of the same table. Those conditions and actions that are critical are connected directly to other conditions and actions, whereas those conditions that do not matter are absent. In other words, the tree does not have to be symmetrical. Third, compared with decision tables, decision trees are more readily understood by others in the organization. Consequently, they are more appropriate as a communication tool.
Child Diagram:
The diagram that results from exploding the process on Diagram 0
Context-Level Data Flow Diagram:
The most basic data flow diagram of an organisation showing how processes transform incoming data into outgoing information
6. What is the advantage of using structured English to communicate with people in the organization?
The obvious advantage of clarifying the logic and relationships found in human languages, structured English has another important advantage: It is a communication tool. Structured English can be taught to and hence understood by users in the organization, so if communication is important, structured English is a viable alternative for decision analysis.
16. In which two situations are decision trees preferable?
The sequence of conditions and actions is critical, When not every condition is relevant to every action (the branches are different).
7. Which quadrant of the decision table is used for conditions? Which is used for condition alternatives?
The upper left quadrant contains the condition(s). The upper right quadrant contains the condition alternatives.
14. In which two situations should you use structured English?
There are many repetitious actions Communication to end users is important.
Four Resource Control Variables of Agile Modeling
Time, Cost, Quality, Scope
1.List three reasons for producing process specifications
To reduce the ambiguity of the process. This goal compels the analyst to learn details about how the process works. Any vague areas should be noted, written down, and consolidated for all process specifications. These observations form a basis and provide the questions for follow-up interviews with the user community. To obtain a precise description of what is accomplished, which is usually included in a packet of specifications for the programmer. To validate the system design. This goal includes ensuring that a process has all the input data flow necessary for producing the output. In addition, all input and output must be represented on the data flow diagram.
Which is the correct choice?
Use decision trees when the sequence of conditions and actions is critical.
Unified Modeling Language (UML)
a language that provides a standardized set of tools to document the object-oriented analysis and design of a software system
What is a more precise way to define the content of an XML document?
a schema
Use Case
a sequence of transactions in a system, the purpose is to produce something of value to an actor in the system
Which of the following may be created by transforming an XML document?
a web page, a portable document format (PDF) file, and output for a handheld device
Data structures are described using __________ notation?
algebraic
An analyst may develop the data flow diagram using a top-down method by using:
algebraic notation and structural records
A(n) __________ is a synonym or another name for the element, used by different users of a system.
alias
Data stores are used to store:
all base elements and some derived elements
What is not a characteristic of the ideal data dictionary?
all base elements on an output data flow must be present on a data flow into the process
Which of the following is a flaw in the system design that is detected by analyzing the data dictionary entries?
all base elements on an output data flow must be present on a data flow into the process.
When drawing the tree, systems analysts do not have to identify:
all outcomes.
When selection is indicated for elements in the data dictionary:
an IF...THEN...ELSE structure must be present in the structured English statements.
Prototyping
an information-gathering technique useful in seeking; User reactions, Suggestions, Innovations, Revision plans
Structured Decision
are those for which the conditions, condition alternatives, actions, and action rules can be determined. There are three major methods for analysis of structured decisions: structured English, decision tables, and decision trees.
Decision tree
are used when complex branching occurs in a structured decision process. Trees are also useful when it is essential to keep a string of decisions in a particular sequence.
What become(s) important for large systems that produce several thousand data elements requiring cataloging and cross-referencing?
automated data dictionaries
Which of the following is included in a physical data structure?
codes that identify the status of a master record
Which of the following is not one of the three basic constructs used to code computer programs?
computation
A(n) __________ element is one that has a smooth range of values.
continuous
In a decision table, ________ occur(s) when rules suggest different actions but satisfy the same conditions.
contradictions
What is a reference work of data about data compiled by systems analysts?
data dictionary
A(n) __________ is composed of related elements.
data structure
A(n) __________ value for an element is one that has certain fixed values.
discrete
A default value on a GUI screen may be used for:
drop-down lists, radio buttons, and check boxes
The symbol X(8) represents
eight alphanumeric characters
What does this symbol represent [ ]?
either/or alternative
The correct determination of a(n) __________ length is important to avoid truncation.
element
When determining the length for elements
figure the amount of a numeric element and add a few characters for a reasonable expansion
Which of the following is not contained in the repository?
generated computer code
A data flow that contains data that are used between processes is called:
internal
Structured English
is based on (1) structured logic, or instructions organized into nested and grouped procedures, and (2) simple English statements such as add, multiply, and move.
A derived element is one that:
is created by processes as a result of calculations or a series of decision-making statements
A 'varchar' data type:
is used for data that can contain any number of characters (up to the database limit)
Condition
it is in the upper left quadrant of a decision table
Condition alternative
it is in the upper right quadrant of a decision table
Running a section of code over and over again until some condition is met is an example of a
loop.
Since a single data flow may only show part of the collective data, ___________.
many data flows may have to be examined to determine the contents of a data store
Process specifications are sometimes called ________, because they are a small portion of the total project specifications.
minispecs
Which is not one of three main advantages of a decision tree over a decision table?
more correct as a communication tool
Elements on a data flow going into or out from a data store:
must be contained by the data store
Structured English can be more complex if blocks of (instructions) are ________ within each other to show hierarchy.
nested
One of the goals of producing ________ is to validate the system design, including the data flow diagram and the data dictionary.
process specifications
Primitive process specifications are not produced for:
processes for which pre-written code already exists.
Which of the following is not a business rule?
programming language IF statements
Which of the following is not one of the main problems that can occur in developing decision tables?
repetition
A(n) __________ is a large collection of information that is larger than a data dictionary.
repository
Process Specifications
sometimes called minispecs because they are a small portion of the total project specifications are created for primitive processes on a data flow diagram as well as for some higher-level processes that explode to a child diagram. They also may be created for class methods in object-oriented design, and, in a more general sense, for the steps in a use case total project specifications
A(n) __________ is one that is contained within a larger data structure and consists of further subdivisions.
structural record
When structured decisions are not complex, an appropriate technique for analyzing the decision process is the use of ________.
structured English
Level-0 Diagram
the explosion of a context-level DFD that shows from three to nine major processed, important data flows, and data stores of the system under study
Which of the following are part of an XML document type definition?
the number of times an element repeats, an element that is optional, the attributes of an XML element, and (NOT) the rules for transforming the XML document into standard output
What is partitioning, and how is it used?
the process of examining a data flow diagram and determining how it should be divided into collections of manual procedures and collections of computer programs
What are the trade-offs involved in deciding how far data streams should be exploded?
time may be wasted and understandability sacrificed if data flow diagrams are overly complex. On the other hand, if the data flow diagrams are unexploded, errors of omission could occur.
Which of the following is not a goal of producing process specifications?
to reduce the time it takes for a process to run
Which of the following is not a problem when creating decision tables?
too many conditions
Which is structured English not based on?
unstructured logic
A base element is one that:
was initially keyed into the system
