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• copy-back-and-apply-log

  In a single step, restores asingle-file backup specified by the--backup-image option or a backup from the directory specified by the--backup-dir option to a server's data directory and performs anapply-log operation to the restored data to bring them up-to-date. Comparing with a multi-step approach for restoring asingle-file backup (which typically consists of performing the successive steps ofextract,uncompress,apply-log, andcopy-back for restoring compressed image, orextract ,apply-log, andcopy-back for uncompressed image), the command makes the restoration process simpler and faster, and also saves the disk space required.

  The following are some special requirements for different kinds of backup restoration usingcopy-back-and-apply-log:

  • To restore a compressed directory or image, include the--uncompress option in the command line.

  • To restore a single-file backup, besides specifying the location of the backup image with the--backup-image option, also supply with the--backup-dir option the location of a folder that will be used for storing temporary files produced during the restoration process.

  • To restore a single-file incremental backup, assuming the full backup (on which the incremental backup was based) has already been restored:

    • Include the--incremental option in the command line.

    • Specifies the location of the incremental backup image with the--backup-image option

    • Supplies with the--backup-dir option the location of a folder that will be used for storing temporary files produced during the restoration process.

  • Advanced: To restore an incremental backup directory, assuming the full backup (on which the incremental backup was based) has already been restored:

    • Include the--incremental option in the command line.

    • Use either the--backup-dir or--incremental-backup-dir option to specify the incremental backup directory.

  • To restore a backup created with the--use-tts option:

    • See the general requirements described inSection 5.1.4, “Restoring Backups Created with the--use-tts Option”.

    • When restoring a single-file backup created with the option setting--use-tts=with-minimum-locking, the folder specified with--backup-dir is also used for extracting temporarily all the tables in the backup and for performing anapply-log operation to make the data up-to-date before restoring them to the server's data directory.

    • Advanced:When restoring a backup directory created with the option--use-tts=with-minimum-locking, anapply-log operation will be performed on the backup directory. That means the backup taken will be altered during the process, and users might want to make an extra copy of the backup directory before proceeding with the restoration, in order to prevent the loss of backup data in case something goes wrong.

  Also note that:

  • Backups created with the--skip-unused-pages option cannot be restored usingcopy-back-and-apply-log.

  • For image backups taken with MySQL Enterprise Backup 3.8.2 or earlier, per-table.ibd files pointed to by.isl files in a backup are restored bycopy-back-and-apply-log to the server's data directory rather than the locations pointed to by the .isl files.

  • Due to a known issue, when restoring a compressed backup created with MySQL Enterprise Backup 3.9 or earlier and containing any InnoDB tables that were created on the server as compressed tables (by using theROW_FORMAT=COMPRESSED option, theKEY_BLOCK_SIZE= option, or both), do not usecopy-back-and-apply-log; instead, perform anapply-log first, and then acopy-back. See entry for Bug# 17992297 in theMySQL Enterprise Backup 3.10.0 changelog for details.

  At the end of thecopy-back-and-apply-log operation, the filebackup_variables.txt is being created or updated in the data directory. This file contains metadata about the restored contents and is being used by successive single-step restores of incremental backups; it should not be deleted or modified by users.

  For some sample commands for restoring different kinds of backups with thecopy-back-and-apply-log command, seeSection 5.1, “Performing a Restore Operation”.

• copy-back

  Restores files from a directory backup to their original locations within the MySQL server.

  Before restoring ahot backup using thecopy-back command, the backup has to beprepared and made consistent using theapply-log command. SeeSection 5.1.7, “Advanced: Preparing and Restoring a Directory Backup” for details. You can also performapply-log andcopy-back together with a singlecopy-back-and-apply-log command.

  Some clean-up efforts on the target directory for restoration might be needed before performing a full restore (for example, when the backup data is used to set up a new MySQL server or to replace all data of an existing MySQL server). See the discussionshere for details.

  There are some special requirements when restoring backups created with the--use-tts option; seeSection 5.1.4, “Restoring Backups Created with the--use-tts Option” for details.

When restoring a server forreplication purpose, if the backed-up server has used theinnodb_undo_directory option to put the undo logs outside of the data directory, when using the fileserver-my.cnf orserver-all.cnf for the--defaults-file option withcopy-back orcopy-back-and-apply-log, care should be taken to configure correctly theinnodb_undo_directory option in the file. Otherwise, the data or log files on the original server might be overwritten by accident.