Which two properties must every primary key value have?
Quelles sont les deux propriétés que doit avoir toute valeur de clé primaire ?
Answers
AIt must be a number and must be less than 1,000Elle doit être un nombre et être inférieure à 1 000
BIt must be text and must be changed every yearElle doit être du texte et être changée chaque année
CIt must be encrypted and stored in a separate tableElle doit être chiffrée et stockée dans une table séparée
DIt must be unique and must never be empty (NULL)Elle doit être unique et ne jamais être vide (NULL)
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