单选题You discover that your Recycle Bin contains two tables with the same name, MY_TABLE. You also have a table named MY_TABLE in your schema. You execute the following statement: FLASHBACK TABLE my_table TO BEFORE DROP RENAME TO my_table2; What will be the

第1题：

Your Oracle Database 10g is online when you execute the following statement：        SQL>ALTER TABLESPACE MY_TABLESPACE FLASHBACK OFF；   What is the result of executing this statement if the Flashback Database feature is already enabled in the database？（）

• A、 The database does not record flashback logs for MY_TABLESPACE
• B、 The tables residing in MY_TABLESPACE are not protected by the Recycle Bin.
• C、 All the tablespaces except MY_TABLESPACE can be recovered using Flashback Database feature.
• D、 None of the flashback technologies， such as Flashback Table， Flashback Transaction Query and Flashback Version Query can be used to recover individual rows within the objects from MY_TABLESPACE

第2题：

You are performing flashback of the EMPLOYEE table in SCOTT’s schema because some incorrect data was inserted into the table and committed by mistake. Which two clauses will you use in the FLASHBACK TABLE statement for using the Flashback Table feature？ （）

• A、 RESETLOGS
• B、 TO TIMESTAMP
• C、 TO BEFORE DROP
• D、 RENAME TO
• E、 TO SCN

第3题：

You issued the following command：        SQL> DROP TABLE MYTABLE；        SQL> SHOW RECYCLEBIN  The following output is returned：        ORIGINAL NAME RECYCLEBIN NAME               OBJECT TYPE      DROP TIME        ------------- ------------------------------ --------------- --------------------        MYTABLE BIN$04LhcpndanfgMAAAAAANPw==$0     TABLE           2005-01-13：20：11：31  You want to drop the table， MYTABLE， from the Recycle Bin. Which two commands can you issue to accomplish the desired task？（）

• A、 DROP TABLE MYTABLE PURGE；
• B、 PURGE RECYCLEBIN；
• C、 PURGE TABLE MYTABLE；
• D、 PURGE TABLE BIN$04LhcpndanfgMAAAAAANPw==$0；

第4题：

The database administrator of your company created a public synonym called HR for the HUMAN_RESOURCES table of the GENERAL schema, because many users frequently use this table. As a user of the database, you created a table called HR in your schema. What happens when you execute this query? SELECT * FROM HR;（）

• A、You obtain the results retrieved from the public synonym HR created by the database administrator.
• B、You obtain the results retrieved from the HR table that belongs to your schema.
• C、You get an error message because you cannot retrieve from a table that has the same name as a public synonym.
• D、You obtain the results retrieved from both the public synonym HR and the HR table that belongs to your schema, as a Cartesian product.
• E、You obtain the results retrieved from both the public synonym HR and the HR table that belongs to your schema, as a FULL JOIN.

第5题：

You discover that your Recycle Bin contains two tables with the same name， MY_TABLE. You also have a table named MY_TABLE in your schema. You execute the following statement：   FLASHBACK TABLE my_table TO BEFORE DROP RENAME TO my_table2；   What will be the result of executing this statement？（）

• A、 One of the tables is recovered from the Recycle Bin using a First In First Out （FIFO） approach.
• B、 One of the tables is recovered from the Recycle Bin using a Last In First Out （LIFO） approach.
• C、 Both the tables are recovered from the Recycle Bin with one table renamed to MY_TABLE2 and the other to a system-generated name.
• D、 None of the tables are recovered from the Recycle Bin， and the statement returns an error.

第6题：

You are performing flashback of the ORDERS table in the Scott’s schema because some important data is deleted in the table by mistake. The SCN number was 771513 at the time of deletion. You issued the following statement to perform Flashback Table：  SQL> FLASHBACK TABLE ORDERS TO SCN 771513；   What is the prerequisite to perform Flashback Table？（）

• A、 You must configure OMF in your database.
• B、 You must enable block change tracking feature in your database.
• C、 You must enable ROW MOVEMENT feature on the ORDERS table.
• D、 You must use the Flashback Version Query before using the Flashback Table feature.

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第13题：

On Monday， you dropped the DEPT table from your schema and then you re-created the DEPT table in your schema. On Wednesday， you have a requirement to restore the DEPT table from the recycle bin. Which statement is correct？（）

• A、 You cannot restore the DEPT table by using the Oracle Flashback Drop feature because a table with the name DEPT already exists in your schema.
• B、 You can restore the DEPT table by using the Oracle Flashback Drop feature， provided you use the RENAME TO clause.
• C、 You cannot restore the DEPT table by using the Oracle Flashback Drop feature because the contents of the recycle bin are purged every 12 hours by default.
• D、 You can restore the DEPT table by using the Oracle Flashback Drop feature and a system-generated name will be assigned to the restored table.

第14题：

Before a Flashback Table operation, you execute the following command: ALTER TABLE employees ENABLE ROW MOVEMENT; Why would you need this to be executed?（）

• A、Because row IDs may change during the flashback operation
• B、Because the object number changes after the flashback operation
• C、Because the rows are retrieved from the recycle bin during the flashback operation
• D、Because the table is moved forward and back to a temporary during the flashback opertion

第15题：

You discover that your Recycle Bin contains two tables with the same name, MY_TABLE. You also have a table named MY_TABLE in your schema. You execute the following statement: FLASHBACK TABLE my_table TO BEFORE DROP RENAME TO my_table2; What will be the result of executing this statement?（）

• A、One of the tables is recovered from the Recycle Bin using a First In First Out (FIFO) approach.
• B、One of the tables is recovered from the Recycle Bin using a Last In First Out (LIFO) approach.
• C、Both the tables are recovered from the Recycle Bin with one table renamed to MY_TABLE2 and the other to a system-generated name.
• D、None of the tables are recovered from the Recycle Bin, and the statement returns an error.

第16题：

Which two statements are correct regarding the Oracle Flashback Drop feature？ （）

• A、 Recycle bin exists for the tables only in non-SYSTEM， locally managed tablespaces.
• B、 You can flash back a dropped table provided row movement has been enabled on the table.
• C、 If you drop an index before dropping its associated table， then the recovery of the index is not supported when you flash back the dropped table.
• D、 When you execute the DROP TABLESPACE？ INCLUDING CONTENTS command， the objects in the tablespace are places in the recycle bin.
• E、 When a dropped table is moved to the recycle bin， only the table is renamed to a system-generated name； its associated objects and constraints are not renamed.
• F、 If you drop a table that is protected by the recycle bin， then associated bitmap-joined indexes and materialized view logs are also stored in the recycle bin.

第17题：

Flashback Database is enabled in your Oracle 10g database. One of your database users erroneously purged an important table residing in his schema. The table was purged sometime between 10：00 P.M. and 10：30 P.M. The next day， you decide to flash back the database. Before you flash back the database， you want to ensure that you have all the necessary flashback data. Which dynamic performance view must you use to determine whether you have the required flashback data to recover the purged table？（）

• A、 V$DATABASE
• B、 V$UNDOSTAT
• C、 V$FLASHBACK_DATABASE_LOG
• D、 V$FLASHBACK_DATABASE_STAT

第18题：

Examine the statement: Create synonym emp for hr. employees; What happens when you issue the statement? （）

• A、An error is generated.
• B、You will have two identical tables in the HR schema with different names.
• C、You create a table called employees in the HR schema based on you EMP table.
• D、You create an alternative name for the employees table in the HR schema in your own schema.

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