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Keys: Super, Candidate, Primary

This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.

State

Attributes combining to uniquely identify tuples form superkeys; minimal superkeys are candidate keys; one candidate is selected as the primary key — the unique identifier for each record.

Show

A vehicle table offers two candidates — identification number, or plate with state — and crowns one.

Watch for

Minimal means no spare attributes riding along.