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 河南成教 / 数据库原理与应用
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[单选题] 定义数据库表中指定列上插入或更新的数值必须在另一张被参照表中的特定列上存在，这属于哪种约束()


A.DEFAULT约束

B.CHECK约束


C.PRIMARY KEY约束


D.FOREIGN KE
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数据库原理与应用
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