Which statements listed below describe the data dictionary views?
1. These are stored in the SYSTEM tablespace
2. These are the based on the virtual tables
3. These are owned by the SYS user
4. These can be queried by a normal user only if O7_DICTIONARY_ACCESSIBLILITY parameter is set to TRUE
5. The V$FIXED_TABLE view can be queried to list the names of these views
A. 1 and 3
B. 2,3 and 5
C. 1,2, and 5
D. 2,3,4 and 5
1,3 它们都被存在 system 表空间以及 owner 都是 sys 用户
2 动态性能视图以基于数据库服务器内部的内存结构构建的虚拟表为基础
4 O7_DICTIONARY_ACCESSIBILTY 设置为 TRUE，则如果用户授予了如 select any table 等权限，即使不是 dba 或sysdba 用户也可以访问数据字典。设置为 FLASE，则普通用户不能访问
5 V$FIXED_TABLE 只能查询动能性能视图所有的名称。