You are responsible for a data warehouse application that uses records from an external table to update one of the dimension tables periodically. The records in the external table may contain data for new rows in the dimension table， or for updates to its existing rows. Which type of SQL command would you use to transfer the data from the external table to the dimension table as efficiently as possible？（）

单项选择题WhatdoestheMetadataApplicationProgrammingInterface（API）allowyoutodo？（）

A.Repair damaged data dictionary entries.
B.Delete data dictionary information about database objects you no longer need.
C.Extract data definition commands from the data dictionary in a variety of formats.
D.Prepare pseudocode modules for conversion to Java or PL/SQL programs with a Metadata code generator

单项选择题The list below displays four steps that you need to execute in order to switch from the primary database role to the standby database role. Choose the correct order of execution for the steps.（）  1. Shot down and start up the former primary instance without mounting the instance.  2. Issue the ALTER DATABASE COMMIT TO SWITCHOVER TO PHYSICAL  STANDBY command.  3. Issue the ALTER DATABASE MOUNTS STANDBY DATABASE command.  4. End read or update activity on the former primary and standby database.

A.1，2，3，4
B.3，2，4，1
C.4，2，1，3
D.4，3，2，1

单项选择题In the Oracle9i Data Guard architecture， what is the purpose of the Log Transport Services？（）

A.A
B.B
C.C
D.D

单项选择题IfyoucreateyourdatabaseusingOracleManagedFiles（OMF），whatistrue？（）

A.You must use Oracle predefined names to identify raw partitions that will hold OMF structures. 
B.You must define directories for two online redo log groups and three copies of the control file. 
C.If your CREATE DATABASE command fails, any OMF database files that have already been created will be dropped automatically. 
D.You must use only OMF data files when adding new tablespaces or data files to your database in the future.

多项选择题WhichthreeattributesoftheLOG_ARCHIVE_DEST_ninitializationparametercontrolthedataavailabilitymodeofaDataGuardstandbydatabase？（）

A.SYNC or ASYNC to identify the network transmission mode. 
B.LGWR or ARCH to identify the primary database process responsible for sending redo information to the standby. 
C.AFFIRM or NOAFFIRM to control whether log archiving disk write operations are to be performed synchronously or asynchronously. 
D.PROTECTED or UNPROTECTED to control the degree of divergence and data loss at the standby database.