單項(xiàng)選擇題

假設(shè)存在表“Student”,表中age列存在null數(shù)據(jù),請(qǐng)問(wèn)下列sql哪個(gè)可以將age為null的數(shù)據(jù)篩選出來(lái):()。

A.select *from Student where age =null;
B.select *from Student where age is null;
C.select *from Student where age =’’;
D.select *from Student where age is ’’;

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