Introduction

Humans have maintained records since the beginning of time. They kept track of births and deaths, tax payments, loan payments, prisoners and crimes, assets, visitors, and even natural disasters. Whether these events were written or transmitted orally, depended on the sophistication of a particular culture.

Through the years, the exponential growth in population, the advent of technology, ease of modern travel, and the emergence of large organizations and bureaucracies led to an explosion in the amount of information and its transfer. Just as it became almost too much for humans to handle all this information, computing started to emerge as a viable way to automate information storage and retrieval. Computers were faster in processing information than any human could, they do not make mistakes if programmed correctly, and they never forget.

Thus computer databases came into existence. A database is simply a collection of related information that is entered into and stored on a computer together with the ways of viewing and analyzing this information. The stored information is called data while the database management system (DBMS) provides ways of viewing, sorting, and analyzing them.

Fig 1a: Examples of Databases

Fig 1a lists some examples of the type of information that may be stored in a database. For instance, when you see a website like Ebay, you will know that a database management system (DBMS) helps them keep track of all their information and display it so well.

Screen Shot 1a: Ebay Listings

What you see in Ebay is a far call from what databases were able to do at the time of their inception in the late 1950s. There were no DBMS then, just large flat files filled with huge amounts of data separated by commas or tab stops and associated customized programs that helped users analyze the data and generate reports. These programs were limited in scope and difficult to change or augment.

In the 1960s, data storage and access needs became momentous; the scope of database projects seemed much larger than anticipated. The Database Management System evolved as an answer to these needs. The first DBMS were marketed by IBM; these were tailored to the organizations that bought them and the sort of data these organizations dealt with. DBMS made it easier for users to manipulate data, take a backup, reorganize files, reclassify data and so on. Researchers have taken great interest in the subject due to the expanding scope and size of database related projects and a unified body of theory and ideas regarding data management grew over the 1960s and 1970s, leading to the birth of the modern generic DBMS.

Fig 1b: Database Timeline

Database management systems have changed a great deal over the last half-century; examining this evolution is a good way to start learning more about DBMS.