【单选题】【消耗次数:1】
SQL中,下列涉及空值的操作,不正确的是___。
age=NULL
ageISNULL
ageISNOTNULL
NOT(ageISNULL)
参考答案:
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相关题目
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①  age=NULL
②  ageISNULL
③  ageISNOTNULL
④  NOT(ageISNULL
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