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Lesson 2 Requirements Analysis
Objective Explain the purpose of Requirements Analysis.

Purpose of Requirements Analysis

The overall purpose of Requirements Analysis is to gather every bit of information needed to design a database that meets the informational needs of an organization. This is accomplished by performing a series of related tasks:
  1. Examine the existing database(s)
  2. Conduct user interviews
  3. Create a data flow diagram (if needed)
  4. Determine user views
  5. Document all findings


As mentioned earlier in this course, Requirements Analysis is the most important and most labor-intensive stage in the DBLC. It is critical for the designer to approach Requirements Analysis armed with a plan for each task in the process.
Experience is the great teacher when it comes to assessing informational needs, but there is no substitute for preparation, specially for new designers.
Most database designers begin Requirements Analysis by examining the existing database(s) to establish a framework for the remaining tasks. Analyzing how an organization stores data about its business objects[1], and scrutinizing its perception of how it uses stored data (for example, gaining familiarity with its business rules)[2] provides that framework.
The database requirements are determined by interviewing both the producers and users of data and using the information to produce a formal requirements specification. That specification includes the data required for processing, the natural data relationships, and the software platform for the database implementation.
For example products, customers, salespersons, and orders can be formulated in the mind of the end user during the interview process.The next lesson defines business objects.
[1] business objects: Items in a business environment that are related, and about which data need to be stored (e.g., customers, products, orders, etc.).
[2]Business rules: A set of rules or conditions describing the business polices that apply to the data stored on a company databases.