052(九)

41、

41.Which two operations can be performed on an external table? (Choose two.) 
A. Create a view on the table 
B. Create an index on the table 
C. Create a synonym on the table 
D. Add a virtual column to the table 
E. Update the table using the UPDATE statement 
F. Delete rows in the table using the DELETE command
Answer: AC 

You can, for example, select, join, or sort external table data. You can also create views and synonyms for external tables. However, no DML operations (UPDATE, INSERT, or DELETE) are possible, and no indexes can be created, on external tables
答案解析

42、

42.Which two statements are true regarding listeners? (Choose two.) 
A. Listeners use only the TCP/IP protocol. 
B. Multiple listener processes can run simultaneously on a host. 
C. Multiple database instances can be registered with a single listener. 
D. The listener-related errors can be traced only at the administrative level. 
E. Only one database instance can be registered with a single listener at any time. 
Answer: BC 

还可以使用IPC协议
多个监听可以同时在一台主机上运行
答案解析

43、

43.Which three statements are correct about temporary tables? (Choose three.) 
A. Indexes and views can be created on temporary tables. 
B. Both the data and the structure of temporary tables can be exported. 
C. Temporary tables are always created in a user's temporary tablespace. 
D. The data inserted into a temporary table in a session is available to other sessions. 
E. Data manipulation language (DML) locks are never acquired on the data of temporary tables. 
Answer: ACE

临时表
Oracle Database temporary tableshold data that exists only for the duration of a transaction or session. Data in a temporary table is private to the session, which means that each session can only see and modify its own data
答案解析

44、

44.You set the following parameters in the parameter file and restarted the database: 
MEMORY_MAX_TARGET=0 
MEMORY_TARGET=500M 
PGA_AGGREGATE_TARGET=90M 
SGA_TARGET=270M 
Which two statements are true about these parameters after the database instance is restarted? (Choose 
two.) 
A. The MEMORY_MAX_TARGET parameter is automatically set to 500 MB. 
B. The PGA_AGGREGATE_TARGET and SGA_TARGET parameters are automatically set to zero. 
C. The value of the MEMORY_MAX_TARGET parameter remains zero until it is changed manually. 
D. The lower bounds of PGA_AGGREGATE_TARGET and SGA_TARGET parameters are set to 90 MB 
and 270 MB, respectively. 
Answer: AD

MEMORY_TARGET:动态控制SGA和PGA时,Oracle总共可以使用的共享内存大小
动态内存管理时,SGA_TARGET和PGA_AGGREGATE_TARGET代表它们各自内存区域的最小设置,要让Oracle完全控制内存管理,这两个参数应该设置为0
答案解析

45、

45.You have issued a SHUTDOWN ABORT command to bring down your database instance. 
Consider the steps that will be performed later when you open the database: 
1. SGA is allocated. 
2. Control file is read. 
3. Redo log files are opened. 
4. Instance recovery is started. 
5. Background processes are started. 
6. Data file headers are checked for consistency. 
7. Server parameter file or the initialization parameter file is read. 
Which option has the correct order in which these steps occur? 
A. 7, 1, 5, 2, 3, 6, 4 
B. 1, 2, 3, 7, 5, 6, 4 
C. 7, 1, 4, 5, 2, 3, 6 
D. 1, 7, 5, 4, 2, 3, 6
Answer: A 

数据库启动的过程
答案解析
原文地址:https://www.cnblogs.com/huanhuanang/p/5342224.html