Se> A column in a databaSe table containing valueS that are alSo found in Some primary key column (of a different table). By extenSion, any reference to entitieS of a different type. Some RDBMSS allow a column to be explicitly labelled aS a foreign key and only allow valueS to be inSerted if they already exiSt in the relevant primary key column. [IS it Still a foregn key if the primary key iS in a different column in the _Same_ table?] (2005-01-14)
