下列关于CREATE UNIQUE INDEX IDX1 ON T(C1，C2)语句作用的说法，正确的是（）。

A . 在C1和C2列上分别建立一个唯一聚集索引 B . 在C1和C2列上分别建立一个唯一非聚集索引 C . 在C1和C2列的组合上建立一个唯一聚集索引 D . 在C1和C2列的组合上建立一个唯一非聚集索引

时间：2022-10-01 15:06:51 所属题库：数据库原理题库

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