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.Obtain a list of datafilesby querying the V$DATAFILE view:SELECT name FROM v$datafile;Then obtain a list of online redo log files for a database using the query below:SELECT member FROM v$logfile;These queries list the datafiles and online redo log files of a database,respectively, according to the information in the current control file of thedatabase.Finally, obtain the names of the current control files of the database by issuingthe following statement within Enterprise Manager:SHOW PARAMETER control_files;Whenever you take a control file backup (using the ALTER DATABASEcommand with the BACKUP CONTROLFILE TO filename option), save a listof all datafiles and online redo log files with the control file backup.To obtainthis list use the ALTER DATABASE command with the BACKUPCONTROLFILE TO TRACE option.By saving the control file backup with theoutput of the TO TRACE invocation, the database s physical structure at thetime of the control file backup is clearly documented.Performing Whole Database BackupsTake a whole database backup of all files that constitute a database after thedatabase is shut down to system-wide use in normal priority.A whole databasebackup taken while the database is open, after an instance crash or shutdown abort is10-2 Oracle8 Backup and Recovery Guide inconsistent.In such cases, the backup is not a consistent whole databasebackup because the files are inconsistent with respect to a current point-in-time.Whole database backups do not require the database to be operated in aspecific archiving mode.A whole database backup can be taken if a databaseis operating in either ARCHIVELOG or NOARCHIVELOG mode.If thedatabase is in NOARCHIVELOG mode, then the backup must be consistent(meaning the database is shut down cleanly before the backup).The set of backup files that result from a consistent whole database backup areconsistent because all files correspond to the same point in time.If a databaserestore is necessary, these files can completely restore the database to an exactpoint in time.After restoring the backup files, you may perform additionalrecovery steps to recover the database to a more current time if the database isoperated in ARCHIVELOG mode.Also, you can take inconsistent wholedatabase backups if your database is in ARCHIVELOG mode.Warning: A backup control file created during a whole database backupshould only be used with the other files taken in that backup, to restore thebackup.It should not be used for complete or incomplete database recovery.Unless you are taking a consistent whole database backup, you should back upyour control file using the ALTER DATABASE command with the BACKUPCONTROLFILE option.See also: For more information about backing up control files, see PerformingControl File Backups on page 10-9.Preparing to Take a Consistent Whole Database BackupTo guarantee that a database s datafiles are consistent, always shut down thedatabase with normal or immediate priority before making a whole databasebackup.Never perform a whole database backup after an instance failure orafter the database is shut down with abort priority (that is, using aSHUTDOWN ABORT statement) unless your database is in ARCHIVELOGmode.In this case, the datafiles are probably not consistent with respect to aspecific point-in-time.To Prepare for a Whole Database Backup:1.Shut down the database with normal or immediate priority.To make a whole database backup, all database files must be closed byshutting down the database.Do not make a whole database backupwhen the instance is aborted or stopped because of a failure.Reopen thedatabase and shut it down cleanly first.Performing Operating System Backups 10-3 2.Back up all files that constitute the database.Use operating system commands or a backup utility to make backups ofall datafiles, and a single control file of the database.Also back up theparameter files associated with the database
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