A Scores column contains 80, 60, NULL and 40 for four candidates, the NULL being an absent candidate. What does SELECT AVG(Score) return?
Une colonne Score contient 80, 60, NULL et 40 pour quatre candidats, le NULL correspondant à un candidat absent. Que renvoie SELECT AVG(Score) ?
Answers
A4545
BNULLNULL
C6060
D00
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