多选题Which two statements are true about checkpointing（）AThe checkpoint frequency decreases with the smaller redo log file size.BIt ensures that all committed data is written to the data files during normal shutdown.CThe frequent full checkpoint in a databa

第1题：

The instance abnormally terminates because of a power outage.  Which statement is true about redo log filesduring instance recovery（）

• A、Inactive and current redo log files are required to accomplish recovery.
• B、Online and archived redo log files are required to accomplish instance recovery.
• C、All redo log entries after the last checkpoint are applied from redo log files to data files.
• D、All redo log entries recorded in the current redo log file until the checkpoint position are applied to data files

第2题：

Which  statements are true about checkpointing（）

• A、The checkpoint frequency decreases with the smaller redo log file size.
• B、It ensures that all committed data is written to the data files during normal shutdown.
• C、The frequent full checkpoint in a database can cause the overall degradation of the database performance.
• D、It prompts the Checkpoint （CKPT） process to write data to the data files and redo information to the onlineredo log files

第3题：

第4题：

Which three statements are true about the stages of database startup？（）

• A、Data files and redo log files can be renamed at the MOUNT stage.
• B、Control files are read at the OPEN stage for the location of data files.
• C、Control files are required to bring the database to the NOMOUNT stage.
• D、Data files and redo log files are made available to users at the OPEN stage.
• E、Data files and online redo log files are checked for consistency while opening the database

第5题：

You performed the RMAN database backup with the KEEP option.Which two statements are true about this backup?（） (Choose two)

• A、The KEEP option overrides the configured retention policy
• B、The KEEP option is an attribute of an individual backup piece
• C、The backup contains only data files and archived redo log files
• D、The backup contains data files, the server parameter file and the control file even if the control file auto backup is disabled

第6题：

Which statement is true regarding the Archiver （ARCn） process，archived log files，and recovery？ （）

• A、A database backup, combined with archived redo log files, guarantees that all committed data can be recovered to the point of failure. 
• B、During recovery the ARCn background process copies its redo entries identified for recovery by the control file to the data files. 
• C、After each write to an archived log, the mandatory background process ARCn writes its log sequence number and the first and last SCN number within the log sequence to the control file. 
• D、At database recover time, and archived redo log is uniquely identified for recovery use by its redo thread number and destination ID number retrieved from the control file.

第7题：

After performing a clean shut down of the database instance for maintenance， you mount the database andthen execute a command to open the database：SQL> ALTER DATABASE OPEN； Which two statements are true（）

• A、The online redo log files and online data files are opened.
• B、All the online data file headers are checked for consistency.
• C、Instance recovery is performed before opening the database.
• D、The path and existence of all the log file members are checked

第8题：

第9题：

Which two statements are true about checkpointing（）

• A、The checkpoint frequency decreases with the smaller redo log file size.
• B、It ensures that all committed data is written to the data files during normal shutdown.
• C、The frequent full checkpoint in a database can cause the overall degradation of the database performance.
• D、It prompts the Checkpoint （CKPT） process to write data to the data files and redo information to the online redo log files.

第10题：

The instance abnormally terminates because of a power outage. Which statement is true about redolog files during instance recovery（）

• A、Inactive and current redo log files are required to accomplish recovery.
• B、Online and archived redo log files are required to accomplish instance recovery.
• C、All redo log entries after the last checkpoint are applied from redo log files to data files.
• D、All redo log entries recorded in the current redo log file until the checkpoint position are applied to datafiles.