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Properly expressing foreign keys (which means understanding the possible semantic subtleties involved in various alternatives), singles out mastery of the data modeling process. And truly ...
For everyone normalizing their designs, just remember: There ain't no such thing as a partial foreign key. When a project pretends that partial foreign keys are a valid concept, the end result is a ...
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 ...