RMU Restore rebuilds a database from a backup file, produced
earlier by an RMU Backup command, to the condition the database
was in when the backup operation was performed and attempts to
automatically recover the .aij files to provide a fully restored
and recovered database.
You can specify only one backup file parameter in an RMU Restore
command. If this parameter is a full backup file, you cannot use
the Incremental qualifier. However, you must use the Incremental
qualifier if the parameter names an incremental backup file.
RMU Restore attempts automatic .aij file recovery by default when
you issue a database restore command if you are using fixed-
size .aij files, if .aij files have been retained, and if a
database conversion has not been performed. (The .aij files are
not retained when you specify any of the following qualifiers:
Aij_Options, After_Journal, or Duplicate.) RMU Restore does not
attempt automatic .aij file recovery if you have backed up any
of your .aij files (using the RMU Backup After_Journal command)
because RMU Restore has no knowledge of those backup files.
In addition, success of the automatic .aij file recovery
operation requires that the following criteria be met:
o Fixed-size after-image journaling is in effect.
o The .aij files must be on disk (not on tape).
o The .aij files must not have been marked as inaccessible at
the time the database backup operation was performed.
o The .aij files must exist and have proper privileges for both
read and write operations.
o The .aij files must be able to be accessed exclusively;
failure indicates that an .aij file is in use by another
database user.
o The .aij files must have a nonzero length.
o The .aij files must have valid header information that
corresponds to the current Oracle Rdb product and version
number.
o The sequence number in the .aij file header must not conflict
with the restored definition in the database root information.
o The original .rdb file name must not exist.
NOTE
RMU Restore attempts automatic .aij file recovery when you
restore a database from a full, incremental, by-area, or
by-page backup file. However, in some cases, you will want
to disable this feature by using the Norecovery qualifier.
Specifically, you should specify the Norecovery qualifier if
either of the following are true:
o You are restoring the database from a previous version of
Oracle Rdb.
o You need to issue more than one RMU Restore command to
completely restore the database.
For example, if you intend to restore a database by
first issuing a full RMU Restore command followed by
the application of one or more RMU Restore commands with
the Incremental or Area qualifiers, you must specify the
Norecovery qualifier on all but the last RMU Restore
command in the series you intend to issue. Allowing
Oracle RMU to attempt automatic recovery with a full
restore operation when you intend to apply additional
incremental, by-area, or by-page backup files can result
in a corrupt database.
RMU Restore does not attempt automatic .aij file recovery if any
of the following conditions are true:
o The database has been converted since the time you created the
backup file that you are attempting to restore.
o The first .aij file is not available (perhaps because it has
been backed up).
o After-image journaling was disabled when the backup operation
was performed.
o After-image journaling was disabled when the database (or
portion of it) was lost.
o You specify the Aij_Options, After_Journal, or Duplicate
qualifier with the RMU Restore command.
If RMU Restore attempts automatic .aij file recovery but fails,
you can still recover your database by using the RMU Recover
command if the restore operation was successful.
NOTE
Using the DCL COPY command with a multifile database
(assuming the files are copied to a new location) will
result in an unsupported, unusable database. This happens
because the DCL COPY command cannot update the full file
specification pointers (stored in the database root file) to
the other database files (.rda, .snp, and optional .aij).
You can rename or move the files that comprise a multifile
Oracle Rdb database by using one of the following commands:
o The RMU Backup and RMU Restore commands
o The SQL EXPORT and IMPORT statements
o The RMU Move_Area command
o The RMU Copy_Database command
By default, RMU Restore integrates the metadata stored in the
database root (.rdb) file with the data dictionary copy of the
metadata (assuming the data dictionary is installed on your
system). However, you can prevent dictionary integration by
specifying the Nocdd_Integrate qualifier.
When you specify the Incremental or Area qualifiers, do not
specify the following additional qualifiers:
Directory
Nodes_Max
New_Version
Nonew_Version
Users_Max
The RMU Restore command ignores the Confirm qualifier if you
omit the Incremental qualifier. Also, you must specify the Root
qualifier when you restore an incremental backup file to a new
version of the database, renamed database, or a restored database
in a new location.
See the Usage Notes subentry for information on restoring a
database from tape.