zoukankan      html  css  js  c++  java
  • OCP-1Z0-053-V12.02-588题

    588.Which is the correct command to back up the database, back up the archived redo logs, and then

    remove the backed-up archived redo logs?

    A. backup database

    B. backup database and archivelogs

    C. backup database plus archivelogs

    D. backup database plus archivelog delete input

    E. backup database and archivelog delete input

    Answer: D

    参考:http://docs.oracle.com/cd/E11882_01/backup.112/e10643/rcmsynta007.htm#RCMRF90026

    DATABASE Creates a backup of all data files in the database. If generating a backup set, then RMAN can include only data files and control files: it cannot include archived redo log files.

    If the backupSpec includes data file 1, and if CONFIGURE CONTROLFILE AUTOBACKUP is OFF, then RMAN automatically includes the control file in the backup. If the instance is started with a server parameter file, then RMAN also includes this parameter file in the backup.

    If the backupSpec includes data file 1, and if CONFIGURE CONTROLFILE AUTOBACKUP is ON, then RMAN does notautomatically include the control file in the output. Instead, RMAN generates a separate control file autobackup piece. If the instance is started with a server parameter file, then RMAN includes this parameter file in the autobackup piece.

    Full database backups should usually be either image copies or compressed backup sets. Image copies are more flexible than backup sets for some purposes (such as use in an incrementally updated backups strategy), and compressed backup sets make more efficient use of storage space, if the CPU overhead involved in creating them is tolerable.

    Note: To force RMAN to include the current control file in the backup when CONTROLFILE AUTOBACKUP is ON, specify the INCLUDE CURRENT CONTROLFILE clause.

    See Also: The TABLESPACE description to learn about backup behavior when the database includes bigfile tablespaces 


     PLUS ARCHIVELOG Includes archived redo log files in the backup (see Example 2-15). Causes RMAN to perform the following steps:
    1. Run an ALTER SYSTEM ARCHIVE LOG CURRENT statement.

    2. Run the BACKUP ARCHIVELOG ALL command. If backup optimization is enabled, then RMAN only backs up logs that have not yet been backed up.

    3. Back up the files specified in the BACKUP command.

    4. Run an ALTER SYSTEM ARCHIVE LOG CURRENT statement.

    5. Back up any remaining archived redo log files. If backup optimization is not enabled, then RMAN backs up the logs generated in step 1 plus all the logs generated during the backup.

    You cannot specify PLUS ARCHIVELOG on the BACKUP ARCHIVELOG command or BACKUP AS COPY INCREMENTALcommand (or BACKUP INCREMENTAL command when the default backup type is COPY). You cannot specify PLUS ARCHIVELOG when also specifying INCREMENTAL FROM SCN.

    Unless the online redo log is archived after the backup, DUPLICATE is not possible with this backup.  

    DELETE [ALL] INPUT Deletes the input files after successfully backing them up.

    Specify this option only when backing up archived redo log files, data file copies (COPY OF or DATAFILECOPY), or backup sets. The BACKUP ARCHIVELOG command only backs up one copy of each distinct log sequence number, so if the DELETE INPUT option is used without the ALL keyword, RMAN only deletes the copy of the file that it backs up.

    Specifying the DELETE INPUT option is equivalent to issuing the DELETE command for the input files. When backing up archived redo log files, RMAN uses the configured settings to determine whether an archived redo log can be deleted (CONFIGURE ARCHIVELOG DELETION POLICY TO BACKED UP).

    The ALL option applies only to archived redo log files. If you run DELETE ALL INPUT, then the command deletes all copies of corresponding archived redo log files or data file copies that match the selection criteria in theBACKUP command (as shown in Example 2-19). For example, if you specify the SEQUENCE n clause, then RMAN deletes all archived redo log files with same sequence number n.

    Note: The database retains archived redo log files in the fast recovery area as long as possible and deletes them automatically when disk space is required. You can use the BACKUP DELETE INPUTDELETE ARCHIVELOG, andDELETE OBSOLETE commands to delete log files manually from inside or outside the recovery area. You do not need to specify BACKUP DELETE INPUT when backing up the recovery area because the database automatically deletes log files based on the archived redo log deletion policy and other fast recovery area rules. 

    Example 2-19 Backing Up and Deleting Archived Redo Log Files

    This example assumes that you have two archiving destinations set: /disk2/PROD/archivelog/ and /disk1/arch/. The command backs up one archived redo log for each unique sequence number. For example, if archived redo log 1000 is in both directories, then RMAN only backs up one copy this log. The DELETE INPUTclause with the ALL keyword specifies that RMAN should delete all archived redo log files from both archiving directories after the backup.

    BACKUP DEVICE TYPE sbt
      ARCHIVELOG LIKE '/disk%arc%'
      DELETE ALL INPUT;
  • 相关阅读:
    JavaStript基础 —— JavaStript语法
    JS拖动滑块验证
    解释型语言和编译型语言、弱类型语言和强类型语言、动态语言和静态语言的区别
    user-select 用户禁止选中
    短地址
    JS实现 Tab栏切换案例
    setAttribute()方法和 getAttribute() 方法
    JS 全局作用域和局部作用域
    数组遍历 forEach 方法
    十进制小数转换为二进制
  • 原文地址:https://www.cnblogs.com/hzcya1995/p/13316407.html
Copyright © 2011-2022 走看看