ITPub博客

首页 > Linux操作系统 > Linux操作系统 > 043-104

043-104

原创 Linux操作系统 作者:jbymy2000 时间:2012-03-08 09:07:46 0 删除 编辑
104. Exhibit:

View the Exhibits.
You performed operations on the DEPT4 table as shown in the Exhibit.
When you perform. the Flashback Versions Query, you find that the firs
t two updates are not listed.
What could be the reason?
A. The row movement is not enabled on the table.
B. The first two updates were not explicitly committed.
C. The Flashback Versions Query lists only the most recent update.
D. The Flashback Versions Query stops producing rows after it encount
ers a time in the past when the table structure was changed.
Answer: D
在哪种情况下可以使用flashback versions query
a、只能是commited 以后的数据
b、只能是dml 语句,ddl 不行,ddl 以后,前面的dml 也查询不到
c、没必要非要启用row movement

来自 “ ITPUB博客 ” ,链接:http://blog.itpub.net/11312660/viewspace-718018/,如需转载,请注明出处,否则将追究法律责任。

上一篇: 043-103
下一篇: 043-105
请登录后发表评论 登录
全部评论

注册时间:2012-01-10

  • 博文量
    416
  • 访问量
    214088