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【OCP-12c】2019年CUUG OCP 071考试题库(75题)

时间:2019-03-11 14:59:39      阅读:228      评论:0      收藏:0      [点我收藏+]

标签:prim   const   none   apply   one   upd   auto   dex   def   

75、Which statements are correct regarding indexes? (Choose all that apply.)

A. A non-deferrable PRIMARY KEYor UNIQUE KEYconstraint in a table automatically attempts to creates a unique index.

B. Indexes should be created on columns that are frequently referenced as part of any expression.

C. When a table is dropped, the corresponding indexes are automatically dropped.

D. For each DML operation performed, the corresponding indexes are automatically updated.

Correct Answer: ACD

Section: (none)

Explanation:解析,有点数据库管理的意思

【OCP-12c】2019年CUUG OCP 071考试题库(75题)

标签:prim   const   none   apply   one   upd   auto   dex   def   

原文地址:https://blog.51cto.com/13854012/2361161

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