Primary key attributes or columns automatically migrate from a parent to child entity or table when you connect them using a relationship. You can specify, for an individual relationship, that the alternate key attributes or columns migrate to the child entity or table as a foreign key instead of the primary key attributes or columns.
You can see the migrated attributes or columns in the child entity or table when you select the Foreign Key Designator (FK) and Show Migrated Attributes check boxes in the Diagram editor. You can also set these options by right-clicking the model background and using the Entity Display and Table Display shortcut menu options.
When you forward-engineer your model to generate a database schema and you migrate an alternate key (AK) instead of a primary key (PK), a foreign key constraint will not be generated if your target DBMS does not support the referencing of an alternate key by a foreign key.
If you delete the alternate key that you migrate, or if you change the alternate key into an inversion entry (IE) index, the primary key group is used to migrate attributes or columns.
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