database

A database stores information an application will need again, such as customer accounts, orders, appointments or measurements. The application usually works through a database management system, often abbreviated to DBMS. It processes commands to read, add, update or delete data.

How is data organized in a database?

The structure is defined in a data modelGlossary · In briefdata modelA data model describes which data a system records, how that data is related and which rules it must satisfy.Read more. A relational database, for example, divides data into tables with rows and columns. Relationships connect an order to the correct customer or a payment to its invoice. Other databases store information as documents, key-value pairs or graphs.

Software accesses the data through a queryGlossary · In briefqueryA query is a targeted instruction to a system to retrieve, filter, combine or modify data.Read more. A query can find one customer, select all outstanding invoices or save a new address. Database rules can also ensure required data is present and relationships remain valid. A transaction applies related changes as a whole or rolls them all back.

Database or standalone file?

A spreadsheet or text file can also contain data. A database is particularly useful when an application needs targeted searches, processes large amounts of data or allows several users to make changes at once. The management system handles concurrent access, indexes and permissions, among other things.

A database does not automatically prevent errors or data loss. That requires an appropriate data model, validation, security and backups. The right type of database depends on the structure of the data and how the application uses it.