考试科目：1Z0-082

考试题量：90

通过分数：60%

官方考试说明：https://education.oracle.com/产品目录-ouexam-pexam_1z0-082/pexam_1Z0-082

1.Which two statements are true about space-saving features in an Oracle Database? 

A.An index created with the UNUSABLE attribute has no segment.

B.Private Temporary Tables(PTTs) store metadata in memory only.

C.Private Temporary Tables(PTTs) when used, are always dropped at the next commit statement. D.An index that is altered to be UNUSABLE will retain its segment

E. A table that is truncated will always have all of its extents removed

答案：AB

https://docs.oracle.com/en/database/oracle/oracle-database/18/admin/managing-tables.html#GUID-8A4441BC-9B9E-46AA-9CEE-D825440F34C7

经过测试，truncate table初始的extent不会删除。

经过测试alter index in_a unusable;会删除所有的segment。

2.Which two statements are true about views?

A.A view must only refer to tables in its defining query.

B.The WITH CHECK clause prevents certain rows from being displayed when querying the view C.Views can be updated without the need to re-grant privileges on the view

D.The WITH CHECK clause prevents certain rows from being updated or inserted in the underlying table through the view. 

E.Views can be indexed

答案：CD

a也可以用视图

3.Examine the description of the products table

A.SELECT prod_id, AVG(MAX (cost)) FROM products GROUP BY prod_id. 

B.SELECT prod_id, MAX (AVG (cost)) FROM products GROUP BY prod_id: 

C.Select prod_id, release_date, SUM(cost) FROM products GROUP BY prod_id

D.SELECT prod_id, release_date, SUM(cost) FROM products GROUP BY prod_id, release_date

答案：D

没有出现在分组函数中的列必须出现在 group by 子句中

4.You currently have an active transaction in your session and have been granted select access  to V$TRANSACTION

In which three situations will re-executing this query still return a row but with a different XID indicating a new transaction has started?

A.after successfully executing a TRUNCATE statement followed by a DML statement

B.after successfully executing a CREATE TABLE AS Select statement followed by a SELECT FOR UPDATE statement

C.after successfully executing a CREATE TABLE statement followed by a CREATE INDEX statement

D.after successfully executing a commit or ROLLBACK followed by a DML statement 

E.after successfully executing a DML statement following a failed DML statement

F. after successfully executing a commit or ROLLBACK followed by a Select statement

答案：ABD

F这个事务会结束，但不会开启一个新的事务。

Followed by的意思和followed相反

5.Which two statements are true about the PMON background process? 

A.It rolls back transactions when a process fails

B.It registers database services with all local and remote listeners known to the database instance 

C.It frees unused temporary segments

D.It frees resources held by abnormally terminated processes 

E.It records checkpoint information in the control file

答案：AD

将数据库服务注册到监听，轮询每60秒（12c后这项工作由LRRG进程负责）

6.Examine the description of the BOOKS_TRANSACTIONS table:


Which two WHERE conditions give the same result?

A.WHERE borrowed_date= SYSDATE AND (transaction_ type ='RM' AND (member_id='A101' OR member_id ='A102' ))

B.WHERE borrowed_date= SYSDATE AND (transaction type='RM' OR member_id IN ('A101', 'A102'))

C.WHERE borrowed_date= SYSDATE AND (transaction type ='RM' AND member_id 'A101' OR member id ='A102')

D.WHERE borrowed_date= SYSDATE AND transaction type ='RM' OR member id IN

('A101', 'A102')

E.WHERE (borrowed date= SYSDATE AND transaction type ='RM') OR member id IN A101','A1021)

答案：DE