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TableTAB1wascreatedusingthefollowingstatement:CREATETABLEtab1(c1INT,c2INT,c3INT,c4INT,c5INT);IfcolumnC1isuniqueandqueriestypicallyaccesscolumnsC1andC2together,whichstatement(s)willcreateindex(es)thatwillprovideoptimalqueryperformance?()

A.CREATEUNIQUEINDEXxtab1ONtab1(c1)include(c2)

B.CREATEUNIQUEINDEXxtab1ONtab1(c1);CREATEINDEXxtab2ONtab1(c3)INCLUDE(c2)

C.CREATEUNIQUEINDEXxtab1ONtab1(c2,c1)

D.CREATEUNIQUEINDEXxtab1ONtab1(c2)INCLUDE(c1)


参考答案

更多 “ TableTAB1wascreatedusingthefollowingstatement:CREATETABLEtab1(c1INT,c2INT,c3INT,c4INT,c5INT);IfcolumnC1isuniqueandqueriestypicallyaccesscolumnsC1andC2together,whichstatement(s)willcreateindex(es)thatwillprovideoptimalqueryperformance?()A.CREATEUNIQUEINDEXxtab1ONtab1(c1)include(c2)B.CREATEUNIQUEINDEXxtab1ONtab1(c1);CREATEINDEXxtab2ONtab1(c3)INCLUDE(c2)C.CREATEUNIQUEINDEXxtab1ONtab1(c2,c1)D.CREATEUNIQUEINDEXxtab1ONtab1(c2)INCLUDE(c1) ” 相关考题
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