SIAA MIDTERM 312

Files

Electronic lists of information formatted for specific transactions, manipulated by programs

Master files

store core information that is important to the business and, more specifically, to the application, such as order information or customer mailing information.

Look-up files

contain static values, such as a list of valid codes or the names of the U.S. states. Typically, the list is used for validation.

transaction file

holds information that can be used to update a master file.

audit file

records “before” and “after” images of data as the data are altered

Database

Collection of related information grouped logically

Legacy Database

databases which are based on older, sometimes outdated technology that is seldom used to develop new applications.

Relational Database

based on collections of tables, each of which has a primary key—a field(s) whose value is different for every row of the table.

Object Database

all things should be treated as objects that have both data (attributes) and processes (behaviors).

Multidimensional Database

a type of relational database that is used extensively in data warehousing.

Selecting a Storage Format

Each data storage format has strengths and weaknesses; projects may use multiple formats simultaneously.

Change entities to tables or files

Beginning with the logical entity relationship diagram, change the entities to tables or files and update the metadata.

Change attributes to fields

Convert the attributes to fields and update the metadata.

Add primary keys

Assign primary keys to all entities.

Add foreign keys

Add foreign keys to represent the relationships among entities.

Add system-related components

Add system-related tables and fields.

Optimizing Data Storage

Methods vary with format selection; includes optimizing storage efficiency, access speed, and estimating storage size.

Optimizing Storage Efficiency

The most efficient tables in a relational database in terms of storage space have no redundant data and very few null values

Optimizing Access Speed

When data from multiple tables must be accessed or queried, the tables first must be joined together.

Estimating Storage Size

one last way to plan for good performance is to apply volumetrics, which means estimating the amount of data that Optimizing Data Storage 433 the hardware will need to support.

Implementation

Phase involving software development, testing, and new operating procedures.

Managing the Program Process

Tasks include assigning programming tasks, coordinating activities, and managing the programming schedule.

Test Planning

has 20 to 30 pages, with a separate page for each individual test in the plan.

Unit Test

to ensure that the module or program performs its function as defined in the program specification.

Integration Test

assess whether a set of modules or programs that must work together do so without error.

System Tests

usually conducted by the systems analysts to ensure that all modules and programs work together without error.

Acceptance Tests

The goal is to confirm that the system is complete, meets the business needs that prompted the system to be developed, and is acceptable to the users.

Designing Documentation Structure

The general structure used in most online documentation, whether reference documents, procedures manuals, or tutorials

Writing Documentation Topics

Topics typically start with very clear titles, followed by some introductory text that defines the topic

Identifying Navigation Terms

The table of contents is usually the most straightforward, because it is developed from the logical structure of the documentation topics

Object-Oriented Design

focus on capturing the structure and behavior of information systems in little modules that encompass both data and processes.

Class

the general template we use to define and create specific instances, or objects.

object

an instantiation of a class.

Methods

implement an object’s behavior.

Messages

information sent to objects to trigger methods.

Encapsulation

combining of process and data into a single entity.

information hiding

suggests that only the information required to use a software module be published to the user of the module.

Inheritance

Subclasses inherit the attributes and methods from the superclass above them.

Polymorphism

the same message can be interpreted differently by different classes of objects.

dynamic binding

Dynamic, or late, binding is a technique that delays identifying the type of object until run-time.

Use Case Driven

use cases are the primary modeling tool employed to define the behavior of the system.

Architecture Centric

the underlying architecture of the evolving system drives the specification, construction, and documentation of the system.

Iterative and Incremental

undergoes continuous testing throughout the life of the project.

Unified Modeling Language, Version 2.0

Provides a common vocabulary for object-based terms and diagramming techniques.

Use Case Diagram

Illustrates system functions, users, actors, use cases, system boundary, and association relationships.

Creating a Use Case Diagram

Involves identifying use cases, drawing the system boundary, placing use cases, identifying actors, and adding association relationships.

Class Diagram

Represents the structure of a system by showing the system's classes, their attributes, methods, and relationships.

Class

The main building block in a class diagram that stores and manages information in the system.

Associations

Relationships between classes depicted by lines in a class diagram.

Generalization and Aggregation

Generalization shows inheritance between classes, while aggregation represents classes comprising other classes.

Views

Subsets of information used to simplify complex class diagrams.

Sequence Diagram

Illustrates objects participating in a use case and messages passing between them over time.

Actor

A person or system external to the system sending/receiving messages in a sequence diagram.

Object

Participates in a sequence by sending/receiving messages in a sequence diagram.

Lifeline

Represents the life of an object during a sequence in a sequence diagram.

Message

Conveys information between objects in a sequence diagram.

Object destruction

An X is placed at the end of an object’s lifeline to show that it is going out of existence.

Behavioral State Machine Diagram

Illustrates states, events, transitions, and object behavior changes.

State

Represents the condition of an object in a behavioral state machine diagram.

Event

Triggers a change in state in a behavioral state machine diagram.

Transition

Indicates movement from one state to another triggered by an event in a behavioral state machine diagram.