| Lesson 5 || RelationalDB Analysis Course Project |
| Objective || Describe the database course project. |
Relational Database Course Project
A wide range of skills will be acquired in this course and applied to relational databases.
Those skills will be applicable to the many different types of databases you might be called on to design.
To practice applying these skills, you will complete a project for this course.
The Course project
For the duration of the course, imagine that you are a consultant for a company called Stories on CD.
You will design and create a database to help you to track the orders Stories on CD places with its distributors. This course includes a number of hands-on exercises that enable you to complete these steps incrementally, applying what you learn in the lessons to a real-world situation.
These exercises culminate in the completion of a database to store data about Stories on CD's orders.
This concludes the first module of the course. The next module reviews the basic concepts and terminology of database design and introduces relational constructs. It is important to establish common terminology from the beginning.
Before covering relational databases in more detail, we will briefly cover hierarchical and network database management systems. Understanding their limitations will help you understand the relational approach and how the approach attempts to address these limitations.
One of the hierarchical DBMSs still in use today is an IBM product called IMS, which stands for Information Management System. Its paradigm is to use a tree structure and a series of links to navigate from record type (a table) to record type. Records (single rows) include one or more fields (columns). Each tree must have a single root, or parent record type. The relationship between the record types is the same as the directory structure on your computer: parent to child, continuing onto lower and lower levels. The relationship is maintained as a DBMS pointer structure from one record to another. That pointer is valid for only one level of connectivity, and maintaining the
order of the rows is required for the pointer to work.
This type of data management system has several challenges. One is the direct result of the restriction of being able to link only one parent to any children record types. A hierarchical DBMS (such as IMS) assumes the world can be viewed as a series of unrelated, strictly applied hierarchies, with one parent having many children within a tree structure. When this does not work (and there are many cases when you do not have exclusive classification), you end up with duplication of data across different tree structures. Workarounds for this usually require creating duplicate records or tables to satisfy each different use of the same data, which can lead to data synchronization problems, since the same records appear in numerous places within the database
Database Course Project - Exercise