The Staff table has 200 rows, and 30 staff have no email recorded (NULL). What do COUNT(*) and COUNT(Email) return?
La table Staff a 200 lignes, et 30 agents n'ont pas d'e-mail enregistré (NULL). Que renvoient COUNT(*) et COUNT(Email) ?
Answers
A200 and 200, because both functions count every row in the table200 et 200, car les deux fonctions comptent chaque ligne de la table
B170 and 200170 et 200
C200 and 170200 et 170
D170 and 170170 et 170
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