Flat-file database

The term flat-file describes a very simple model of database, where all the information is stored in a single list, with no nested or linked information. Typically each record (or row) consists of a number of fields (or columns), each containing user data. The data is "flat", as compared to a more complex model such as a relational database.

An example might be a basic phone list, where the database could consist of two fields: Name and Phone Number.

In the 1980's, configurable flat-file database computer applications were popular on MS-DOS and the Macintosh. These programs were designed to make it easy for individuals to design and use their own databases, and were almost on par with word processors and spreadsheets in popularity. Examples of flat-file database products were Filemaker and the shareware PC-File. Some of these offered limited relational capabilities, allowing some data to be shared between files.

Today, there are very few programs designed to allow novices to create and use simple databases. Over time, products like Borland's Paradox, and Microsoft's Access started offering full relational capabilities, as well as built-in programming languages. Low-level database engines like MySQL or Oracle generally require programmers to build applications.

Flat-file database structures are still used internally by many computer applications to store configuration data. Many applications allow users to store and retrieve their own information from flat-files using a pre-defined set of fields. Examples are programs to manage collections of books or appointments.

XML is now a popular format for storing flat-file data.