In relational databases, it is a field in one table that is indexed in another. Foreign keys provide the building blocks for relating tables. For example, in a customer order table, the salesperson field might contain an employee number. That field would be a foreign key in the table, because the employee table would be indexed on employee number. See entity relationship model.
Foreign Keys
Note the \"FK\" indications in this Erwin entity relationship modeling program. Every foreign key is a field in one table that is indexed in another. (Example courtesy of Logic Works, Inc.)
Foreign Keys
Note the \"FK\" indications in this Erwin entity relationship modeling program. Every foreign key is a field in one table that is indexed in another. (Example courtesy of Logic Works, Inc.)
 | Reproduced with permission from Computer Desktop Encyclopedia. Copyright (c) 1981-2009 The Computer Language Company Inc. All rights reserved. |
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