SQL/MX 2.x Installation and Management Guide (H06.10+, J06.03+)

Performing Recovery Operations
HP NonStop SQL/MX Installation and Management Guide—544536-007
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ALTER DISK, ALTNAME and ALTER DISK,
VOLNAME
The only exception to the preceding rule is if the entire database has been consistently
brought down as a unit. For example, suppose that you use ABORT DISK to bring
down all the backup volumes of the mirrored pairs containing SQL/MX objects in a
consistent state. The other mirrored set continues the active database, but the inactive
mirrors also contain a set of consistent SQL/MX objects.
ALTER DISK, ALTNAME and ALTER DISK, VOLNAME
If a volume is renamed inadvertently, reissue the command to rename the volume to its
previous name. If this is not possible, recover the volume only if all the objects on the
renamed volume are described in catalogs on the same volume. If this is the case, use
BACKUP and RESTORE to back up the volume:
1. Identify all the SQL/MX objects to be renamed and all dependencies. Produce
hard-copy reports containing this information.
2. Create an EDIT file containing CREATE CATALOG and ALTER TABLE statements
to re-create the catalogs and reset the security of the catalog tables.
3. Back up the volume by using a file-mode BACKUP command.
4. Use ALTER DISK, ALTNAME to rename the disk. You might first want to label the
disk with ALTER DISK, LABEL to clear the old files.
To restore files:
1. Re-create the catalogs on the renamed volume by using the file created in Step 2
as the input file for the MXCI OBEY command.
2. Restore the files to the disk volume, mapping the old volume names to the new
volume names in the RESTORE command.
3. Map the objects to the new catalogs.
4. Verify the database by using the mxtool VERIFY utility. See the SQL/MX
Reference Manual for command syntax and functionality.
5. SQL compile all programs with new DEFINEs to revalidate the programs. For more
information, see the SQL/MX Programming Manual for C and COBOL.
Caution. ALTER DISK, ALTNAME and ALTER DISK, VOLUME are extremely dangerous
commands because they can corrupt a database. Before using an ALTER DISK command,
perform a STOPOPENS DISK and a CONTROL DISK, REFRESH on the volume to ensure
valid file labels, and then perform a STOP DISK to make the volume inactive.
The ALTER DISK operation renames the files on a volume, but SQL/MX metadata and file
labels still contain the old names. Use it only on disks that contain SQL/MX objects. ALTER
DISK should be used only for volumes that do not contain SQL/MX objects.