Among the properties or attributes of an entity that are stored in columns (fields) in a DBMS table, the identifier is the property that allows one to unambiguously identify each occurrence of the entity and thus to distinguish individuals by assigning them a single value (e.g. the social security number is an identifier property of individuals). In a database, the identifier property is part of the primary key of the table.
See also: Primary Key
[French: Identifiant]