1. Introduction - no DBMS?

Consider how people would store data without a Database Management System (DBMS).

Organisations store all kinds of data in electronic databases:- personnel, wages, sales, finances, stock and so on.

One of the simplest kind of database is a small flat file stored in a spreadsheet.

Perhaps the 'Autofilter' function (the icons in the first row) is used to select a person.

The spreadsheet itself might be unprotected and could be opened by any one with access to the shared drive or computer.

You might use this method to hold local non-confidential data such as department telephone numbers, sales figures or standard holiday times etc.

One level up from this, the spreadsheet might have personal information and so a password is used to protect it.

In the example below their 'home telephone' number is also being stored, as this is personal data, the spreadsheet should be password protected.

But now much more sensitive data needs to be stored - for example salary. How is this going to managed?

One approach would be to start making more and more specialised flat file databases, all stored in different protected shared drives. This soon becomes un-manageable.

This is where the Database Management System comes in.