A Staff table has a column PhoneNumbers containing values like “0788123456, 0722654321”. Which normal form does this break, and why?
Une table Personnel possède une colonne NumérosTéléphone contenant des valeurs comme « 0788123456, 0722654321 ». Quelle forme normale cela enfreint-il, et pourquoi ?
Answers
AThird normal form, because phone numbers depend on the districtLa troisième forme normale, car les numéros dépendent du district
BSecond normal form, because the table has no indexLa deuxième forme normale, car la table n'a pas d'index
CFirst normal form, because a column holds several valuesLa première forme normale, car une colonne contient plusieurs valeurs
DIt breaks no ruleCela n'enfreint aucune règle
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