TABLE OF CONTENTS Even with established, functioning databases, there are many places where good database design (or modification) can result in better, more accurate, and more effective data management. While it is always best to design the database in the planning and development stages, any system can be modified and improved. Therefore, even when dealing with a commercial database product, many of the concepts introduced here will be important in designing, populating, modifying, and using a DBMS. This chapter is devoted to the actual design of a technical database, including planning for the types of data to be stored, how to deal with user activity and record deletions, and the use of CASE (Computer-Aided Software Engineering) tools to design and develop the project.
A data dictionary is a roadmap of the underlying database. In it are stored the names of the tables used, the columns (elements) contained in each table, and the data types and formats for each element in the database. In addition, the data dictionary shows the fundamental relationships between tables, primary and foreign index keys, view definitions, validation rules, and data relation diagrams. The data dictionary is the fundamental reference for the database and forms the basis for implementing and maintaining the database.
The use of data dictionaries has traditionally been limited to the programmers and DBAs responsible for maintaining the database and its contents. However, having a fundamental understanding of the structure and purpose of data dictionaries can help the working geotechnical professional...
