OCP-1Z0-052-V8.02-146题

146. Identify three situations in which you would NOT be able to drop a tablespace. (Choose three.)

A.when the tablespace is online

B.when the tablespace has segments with data in it

C.when the tablespace is a default permanent tablespace for the database

D.when the tablespace contains a table that is currently being used by transactions

E.when the tablespace contains undo data that is needed to rollback an uncommitted transaction

Answer: CDE

答案解析：

A,B答案：

1、创建表空间

sys@TEST0924> create tablespace lxtbs datafile '/u01/app/oracle/oradata/test0924/lxtb01.dbf' size 10m;

Tablespace created.

2、创建表并指定表空间

sys@TEST0924> create table lxtb tablespace lxtbs as select * from scott.emp;

Table created.

sys@TEST0924> select tablespace_name,status,contents from dba_tablespaces;

TABLESPACE_NAME STATUS CONTENTS

------------------------------ --------- ---------

SYSTEM ONLINE PERMANENT

SYSAUX ONLINE PERMANENT

UNDOTBS1 ONLINE UNDO

TEMP ONLINE TEMPORARY

USERS ONLINE PERMANENT

EXAMPLE ONLINE PERMANENT

LXTBS ONLINE PERMANENT

7 rows selected.

sys@TEST0924> select table_name,tablespace_name from dba_tables where table_name='LXTB';

TABLE_NAME TABLESPACE_NAME

------------------------------ ------------------------------

LXTB LXTBS

3、此时插入数据，不提交，然后drop表空间，报错。A,B错

sys@TEST0924> drop tablespace lxtbs;

drop tablespace lxtbs

*

ERROR at line 1:

ORA-01549: tablespace not empty, use INCLUDING CONTENTS option

sys@TEST0924> drop tablespace lxtbs INCLUDING CONTENTS ;

Tablespace dropped.

C答案：

sys@TEST0924> select TABLESPACE_NAME,CONTENTS,LOGGING from dba_tablespaces

2 ;

TABLESPACE_NAME CONTENTS LOGGING

------------------------------ --------- ---------

SYSTEM PERMANENT LOGGING

SYSAUX PERMANENT LOGGING

UNDOTBS1 UNDO LOGGING

TEMP TEMPORARY NOLOGGING

USERS PERMANENT LOGGING

EXAMPLE PERMANENT NOLOGGING

6 rows selected.

sys@TEST0924> drop tablespace USERS;

drop tablespace USERS

*

ERROR at line 1:

ORA-12919: Can not drop the default permanent tablespace

D,E答案

You cannot drop a tablespace that contains any active segments.

For example, if a table in the tablespace iscurrently being used or the tablespace contains undo data needed to roll backuncommitted transactions, you cannot drop the tablespace. The tablespace can be online or offline, but it is best to take the tablespace offline before dropping it.

官方参考：http://docs.oracle.com/cd/E11882_01/server.112/e25494/tspaces.htm#i1007008