单选题By mistake， you ran the batch job （for updating the BILL_DETAILS table） twice. You are not sure which rows in the BILL_DETAILS table were affected. You need to identify：  a） a list of changes made along with the transaction identifier of each change  b

第1题：

At the end of the financial year， an accounts accumulation batch is run. This batch updates the company’s accounting records. During the batch run process， some incorrect entries were inserted into the ACCOUNT table. You identified the bug and immediately stopped the batch run process， but 3000 incorrect records were inserted into the ACCOUNT table before the batch process was stopped. You want to recover the table to the state it was at 11：50 P.M. Which flashback feature will you use？（）

• A、 Flashback Drop
• B、 Flashback Database
• C、 Flashback Table
• D、 Flashback Version Query

第2题：

You executed the following FLASHBACK TABLE command： FLASHBACK TABLE emp TO TIMESTAMP （’11：45’，’hh12：mi’）; Which two statements are correct？（）

• A、The FLASHBACK TABLE statement will not be written to the alert log file.
• B、The changes made to the EMP table since the specified time will be undone.
• C、The EMP table that was dropped by mistake from the database will be restored.
• D、The FLASHBACK TABLE statement will be executed within a single transaction.
• E、The FLASHBACK TABLE statement will not maintain the existing indexes on the EMP table. 
• F、The list of transactions that have modified the EMP table since the specified time will be displayed.

第3题：

第4题：

You are working on an Oracle Database 10g database. For which purposes would you use the Flashback Transaction Query feature？ （）

• A、 To recover a dropped table.
• B、 To recover a dropped schema.
• C、 To recover data from a truncated table.
• D、 To view changes made by all the transactions during a given period of time.
• E、 To view changes made by a single transaction during a given period of time.

第5题：

Which two statements are correct regarding the Flashback Versions Query feature？（）

• A、 You can use this feature to identify the committed versions of the rows， but not the uncommitted versions.
• B、 You can use this feature to identify the versions of V$ views.
• C、 You can use this feature to identify the inserts， deletes， and updates performed on a particular row but not the data definition language （DDL） operations performed on the table.
• D、 You can use this feature for a table only if row movement is enabled for the table.
• E、 You can use this feature to identify the versions of external and fixed tables.

第6题：

By mistake， you ran the batch job （for updating the BILL_DETAILS table） twice. You are not sure which rows in the BILL_DETAILS table were affected. You need to identify：  a） a list of changes made along with the transaction identifier of each change  b） the necessary SQL statements to undo the erroneous changes  Which option would you choose？（）

• A、RMAN only
• B、Flashback Table only
• C、Flashback Versions Query only
• D、Flashback Database and Flashback Transaction Query
• E、Flashback Versions Query and Flashback Transaction Query

第7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8题：

You discover that the schema changes that were recently made to your SQL Server 2005 database have caused your Web site to stop functioning. It is unclear who made the changes. TestKing.com now mandates that all changes to the database schema be tracked. You need to implement a mechanism that will track schema changes in your database.  What should you do？（）

• A、Implement a stored procedure that writes data about schema changes to a log table.
• B、Implement DDL AFTER triggers that write user and schema information to a log table.
• C、Implement a DML INSTEAD OF trigger that writes data about schema changes to a log table.
• D、Implement a DML AFTER trigger that writes data about schema changes to a log table.

第9题：

You need to change the definition of an existing table. The COMMERCIALS table needs its DESCRIPTION column changed to hold varying length characters up to 2000 bytes. The column can currently hold 1000 bytes per value. The table contains 20000 rows. Which statement is valid?（）

• A、ALTER TABLE commercials MODIFY (description CHAR2(2000));
• B、ALTER TABLE commercials CHANGE (description CHAR2(2000));
• C、ALTER TABLE commercials CHANGE (description VARCHAR2 (2000));
• D、ALTER TABLE commercials MODIFY (description VARCHAR2 (2000));
• E、You cannot increase the size of a column if the table has rows.

第10题：

You are working in an online transaction processing （OLTP） environment. You used the FLASHBACK TABLE command to flash back the CUSTOMERS table. Before executing the FLASHBACK TABLE command， the System Change Number （SCN） was 663571. After flashing back the CUSTOMERS table， you realize that the table is not in the correct state and the resultant changes are not what you had desired. So， you need to reverse the effects of the FLASHBACK TABLE command while ensuring that：  a） No other user data in the database is affected.  b） The operation takes the minimum possible time.  Which option would you choose？（）

• A、use the ROLLBACK command with SCN 663571
• B、perform Flashback Transaction Query with SCN 663571
• C、execute the FLASHBACK DATABASE statement to retrieve the CUSTOMERS table as it was at SCN 663571
• D、execute another FLASHBACK TABLE statement to retrieve the CUSTOMERS table as it was at SCN 663571