What does Flat File mean?

A flat file database stores data in plain text format. In a relational database, a flat file includes a table with one record per line. The different columns in a record are delimited by a comma or tab to separate the fields. Unlike a relational database, a flat file database does not contain multiple tables. Data stored in flat files have no folders or paths associated with them.

Flat files are widely used in data warehousing projects to import data. No manipulation is performed on the data they store, but they are preferred due to the ease with which they carry data from the server. Flat files only serve as a bare means of storing table information, but do not hold any relations between the tables included within them.

Techopedia explains Flat File

Programmers use flat file databases when creating applications in Oracle and SQL, which support multiple programming languages. Because of their simple structure, flat files consume less space than structured files, but the information in flat files can only be read, stored and sent. Data representation in a flat file database complies with certain standards. Every column in a flat file database is restricted to a specific data type. Delimiters are included in flat files to ensure fixed-width data formatting. These reduce the overhead of locating different fields in a record. The first row in a flat file refers to the field name. This distinct field name makes it easier to identify what data each field deals with. All rows in a flat file database also follow the tuple concept in relational algebra, where a tuple is an ordered list of elements. Data in flat files exist in their original form until they are transferred into a database management system or staging area in a warehouse. Once the transmission is completed, the data is altered and saved in different forms.