The above is all the slide says but I'm confused about what the violation is, is the referential integrity violation in this example that the non-primary key attributes Country and CompName in the Competitors relation reference the non-primary key attributes of Country and CompName in the Records relation?
So does than mean whenever this happens (non-primary attribute of one relation referencing the non-primary attributes of another relation) that the referential integrity is violated?
Btw, this may just be a typo in the slide but in the competitors table, the Key is a combination of CompId, Country and CompName. As you can see in the above copy of the slide Country and CompName weren't underlined.
Last edited by Castiel; 04-10-10 at 02:57.
Reason: Further clarification
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