What is a database? (types, uses)

Databases are the key to many aspects of online life, and are generally the most efficient was of storing and manipulating data. Most people, however, seem to reach of their favourite spreadsheet application when storing data and in doing so storing date often inefficiently. This article takes a look at what a database is and what types there are.

What is a database?

Definition
A database is a system that stores data on a computer system. They are used all the time by everyone who accesses computer based data and most of the time they are invisible to the end user. The idea behind a database is to provide an efficient storage of related data in a format that allows quick, easy and accurate querying of data. Elements
In a commercial environment databases usually consist of two elements, a server which holds the data and a client which controls access to that data. The client can be anything from a computer game, for example all the data used by World of Warcraft is stored on the server in a database, through to your banking website. There are also standalone database solutions such as a Microsoft access where everything is usually, but not always, stored in the one file, which contains both the data and the client 'front end'.

How do they work?

Tables and fields
When the database was created it was defined as having a number of tables. Within the definition of a database file these tables hold a number of fields, some of which are linked together. A table is simply a definition of a set of related data which can be keyed by a unique field. For example someone's personal details would be linked to their name, or Social security number etc. Another table might hold, for example, their orders with an online company.
Spreadsheet versus database
Within a spread sheet, one complete sheet would be held for each record, and would contain the personal details AND a single order. Trying to find the right order, should a customer have a query, would be slow and if the customer changes their address then all the records need changing. Within a database, each order would have a single field which held the unique/non changing field for the personal details table. Should a customer change their address, then just one record is changed. If a customer needs information on an order, then the database can be queried for just a specific order number. This is a lot quicker than manually sifting through thousands of spreadsheet pages.
Conclusion
In summary databases provide a flexible and accurate way to store and quickly access data for a huge range of tasks.