Databases

A database is a persistent organised store of similar data on a computer system. Persistent means it is stored in secondary storage which means it can be accessed later.


There are different models for database.









Key terms
Serial file: A file of items one after another

Sequential File: A serial file in order

Entity: Something that we store data about in a database

Record: All the data about one item in a database

Attribute: A characteristic of an entity. It becomes a field in a data table.

Field: A characteristic of something stored in a database

Indexed sequential file: A sequential file that is accessed using an index which is separate file.

Flat file database: Database consisting of only one table





A database can be used to hold information in a business e.g. employees salary, employee background. 


Key field: