An e-recruitment system uses a numeric AccountID as primary key, but each email address must also belong to only one account. What should be added to the Email column?
Un système de recrutement en ligne utilise un IDCompte numérique comme clé primaire, mais chaque adresse e-mail ne doit appartenir qu'à un seul compte. Que faut-il ajouter à la colonne Email ?
Answers
AA second primary key on the same table, alongside the AccountID keyUne seconde clé primaire sur la même table, à côté de la clé IDCompte
BA CHECK constraint that the email contains “@gov.rw”Une contrainte CHECK exigeant que l'adresse contienne « @gov.rw »
CA DEFAULT valueUne valeur DEFAULT
DA UNIQUE constraintUne contrainte UNIQUE
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