A database is a collection of files used by an organization in support of its daily operations. The files in a database are commonly called tables because their data is organized into rows and columns. Databases allow for easy storage and retrieval of the data kept within the files that make up the database. Database management software is a collection of applications that allow database administrators to create and manage databases. These applications provide the functions necessary to query, sort, and secure the data stored within a database (Farrell, 2008).
Any database must provide five basic features. The essential feature of databases is the storage of data. Data storage is useless without the ability to retrieve the data when needed. Since most data changes over time, databases must allow users to edit the data. In modern organizations, databases have grown to include thousands, or even millions, of records. Databases offer users the ability to organize data in a method that suits their needs. Finally, databases offer the ability to distribute information derived from the data it contains (Senn, 2004).
Relational Database Concept
In 1970, Dr. Edgar F. Codd first presented the concept of the relational database to the world through an article called "A Relational Model of Data for Large Shared Databanks." Before Codd's breakthrough, various database models had been in production for years. Codd realized that these previous database technologies suffered from various inadequacies that questioned their long-term sustainability. As a mathematician, Codd felt mathematics could be used to evolve data storage to the next level. The concept of relational databases is based on set theory and first-order predicate logic. Using these mathematical branches, Codd was able to address many of the weaknesses of existing database technologies (Hernandez, 2003).
Relational Database Architecture
The organizational structure of a relational database is the relation. Relations hold common sets of data. The unique bits of data within a relation are called a tuples. Tuples are composed of attributes. Therefore, relations are made of tuples, which in turn are made of attributes. More commonly accepted terms for relations, tuples, and attributes are tables, records, and fields, respectively. The architectural feature of relational databases that sets it apart from previous database systems is its independence from the computer's storage medium. Previous database systems required users to understand the underlying storage technology in order to retrieve data. Additionally, relational databases do not require that data be stored in any particular order. Unique fields within each record ensure that data is properly retrieved and may be sorted in anyway the user requires. Finally, relational databases employ a client-server architecture that allows for centralized data storage. This allows the data to be maintained in one location with expert support while users access data remotely (Hernandez, 2003).
Farrell, J. (2008). Programming logic and design, comprehensive (5th ed.). Boston: Thomson Course Technology.
Hernandez, M. J. (2003). Database design for mere mortals: A hands-on guide to relational database design (2nd ed.). Boston: Pearson.
Senn, J. A. (2004). Information technology: Principles, practices, opportunities (3rd ed.). Upper Saddle River, NJ: Pearson.