20151208 再次搭建Oracle11g环境 ocp 047 20-40

重装redhat虚拟机出现了一个情况，忘记了root用户的密码 这里记录一下在字符界面引导更改root用户的密码

启东虚拟机后按e,

按选择kernel /vmlinuz-2.4.20-8 ro root=LABEL=/ 项，按e键，然后“空格” 输入 “single

进入single模式

输入之后b键进入字符引导模式

输入passwd root来更改root用户的密码即可

3.which three tasks can be performed using regular expression support in oracle database 10g?

a.it can be concatenate(连接) two strings.

b.it can be used to find out the total length of the string 

计算长度，不靠谱

c.it can be used for string manipulation and searching operations 搜索

d.it can be used to format the output for a column or expression having string data 格式化

e.it can be used to find and replace operations for a column or expression having string data 替换

6.which two statements are true?

a.the user_synonyms view can provide information about private synonyms.

这个跟共有同义词和私有同义词没什么关系，都可以查到

b.the user system owns all the base tables and user-accessible views of the data dictionary

除了sys用户可以访问基表，其他都不行

c.the user_objexts view can provide information about the tables and views created by the user only

不是当前用户创建，而是当前用户拥有的，不要搞混了

d.distionary is a view that contains the names of all the data distionary views that the user can access

跟c一样的错误

e.dictionary is a view that contains the names of all the data dictionary views that the user can access