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已知关系R(A,B,C),有定义索引的语句:create unique clustered index idxl on R(B)。下列关于idxl的说法,正确的是( )。

A.idxl既是唯一索引,也是聚集索引

B.idxl既是主索引,也是聚集索引

C.idxl既是唯一索引,也是主索引

D.idxl既不是主索引,也不是聚集索引


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更多 “ 已知关系R(A,B,C),有定义索引的语句:create unique clustered index idxl on R(B)。下列关于idxl的说法,正确的是( )。 A.idxl既是唯一索引,也是聚集索引B.idxl既是主索引,也是聚集索引C.idxl既是唯一索引,也是主索引D.idxl既不是主索引,也不是聚集索引 ” 相关考题
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