218.Your database is running in ARCHIVELOG mode. You are performing a user-managed backup of the
DATA1 tablespace. You place the DATA1 tablespace in backup mode by issuing the following statement:
ALTER TABLESPACE data1 BEGIN BACKUP;
While you are performing the backup, an error occurs that causes the instance to terminate abnormally.
Which statement about the DATA1 tablespace is true?
A. The DATA1 tablespace is automatically taken out of backup mode when the instance aborts.
B. If you restart the database, the DATA1 tablespace will be automatically taken out of backup mode when
the database is opened.
C. If you restart the database, the DATA1 tablespace will be automatically taken out of backup mode when
the database is mounted.
D. If you restart the database, the database will not be opened.
Answer: D
答案解析：
验证测试：
1、测试users表空间
sys@TEST0924> alter tablespace users begin backup;
Tablespace altered.
2、模拟断电
sys@TEST0924> shutdown abort;
ORACLE instance shut down.
3、尝试启动，不能打开
sys@TEST0924> startup
ORACLE instance started.
Total System Global Area 3340451840 bytes
Fixed Size 2232960 bytes
Variable Size 3204451712 bytes
Database Buffers 117440512 bytes
Redo Buffers 16326656 bytes
Database mounted.
ORA-10873: file 4 needs to be either taken out of backup mode or media recovered
ORA-01110: data file 4: '+DATA/test0924/datafile/users.260.829650045'
4、在mount状态让其结束备份模式
sys@TEST0924> alter tablespace users end backup;
Tablespace altered.
5、打开数据库
sys@TEST0924> alter database open;
Database altered.