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1. Minimum 150 Word Respond. Topic: Use Cases and Other Techniques

A Part of the Systems Development is the requirement modeling process.  It is here in the process that the “Use case” concept comes into play.  A “use case” is “An activity the system performs, usually in response to a request by a user” (Satzinger).  Use cases are important as “use cases” outline the fundamental, functional requirements or processes needed for the model to work.   Use cases outline what is happening and what is the desired outcome for a certain instance.    Two strategies identify a use case are the “User Goal Technique” and the “Event Decomposition technique”.  Both are useful but each technique comes from a different angle.  The User goal technique is more user oriented while the decomposition technique is more business oriented and covers a broader base.  One could say one technique runs bottom to top while the other runs top to bottom.   Both are very useful techniques that get the job done.   Overall though, it is the event decomposition technique that is more comprehensive.  As the decomposition technique is more business oriented more aspects of the process are taken In to account.  While the user goal technique is valid it may only focuses on a small aspect of the business. For instance, a user goal technique for a purchase would focus on the picking of the product and the paying of the product but may not really be focused on the shipping, logistics, inventory analysis and reordering which the decomposition technique would take into account.

Another Part of modeling process for system development is the use of ERD’s.  ERD stands for Entity Relationship Diagram.  The ERD would map out how data entities are related or interact with each other.  A part that could make up an ERD would be a “class”.  A class is a category or classification used to describe a collection of object.  ERD’s make use of classes in their structure of interactivity.  Classes can make up key parts of the Entity Relationship Diagram

 

Satzinger, J. W. (2011). Systems analysis and design in a changing world, 6th ed. Boston, MA: Cengage Learning, Inc.

-WALTER

2. Minimum 150 Word Respond. Topic: Use Cases and Other Techniques

Hello all,

Uses cases are very important in determining functionality because depending on both the application the use case can always vary very drastically and it is very important to understand how two very similar people can use an application in two very different ways. Personally, every project that I have embarked on always starts with identifying all the possible use cases. The user goal technique determines the objective that the user must complete & an event decomposition determines the events in which the system will ultimately respond to. This technique Identifies the use cases. User goal technique is quite more exhaustive process than user goal technique in as much that it covers more. 

A class is a category and collection of objects and its components are the attributes that the class has. In programming terms a class is an instance of the object and that object has many different types of attributes (state variables) and in Object Oriented Programming (OOP) there are many different types of classes, there can be abstract classes in which they inherit all the methods from another class. There is also the idea of a super class or parent class if you will that all the other children classes inherit their attributes from. The main difference between class diagrams and ERD (Entity Relationship Diagram) is that an ERD's main purpose is to establish relationships for how data is going to flow mainly for the database. Class diagrams better describe the attributes one single class will have not necessarily showing the relationship that each class may have. 

Source: Satzinger, J. W. (2012). Systems Analysis and Design in a Changing World, 6th Edition. [Bookshelf Online]. Retrieved from https://online.vitalsource.com/#/books/9781285404882/ 

-ELLIOT