The desired backup acquisition mode can be selected by specifying the -M option of the database copy utility (pdcopy command). The following table lists the backup acquisition modes.

Table 6-1 Backup acquisition modes

Backup acquisition mode (-M option specification)	Description of mode	Point to which RDAREAs can be restored
Referencing/updating-impossible mode (x)	RDAREAs being backed up cannot be referenced or updated while the backup is being made. Subject RDAREAs must be placed in shutdown and closed status with the pdhold -c command before the backup is made.	Using a backup made in this mode, the database can be restored to the point when the backup was made. If a system log is used, the database can be restored to any synchronization point after the backup was made.
Referencing-permitted mode (r)	RDAREAs being backed up can only be referenced during backup processing; they cannot be updated.
Updatable mode (s)#1	RDAREAs being backed up can be referenced and updated during backup processing.	A database cannot be restored to the point when the backup was made. It can be restored only to a synchronization point subsequent to the point when the backup was made. Therefore, database restoration requires both the backup and the system log#2 from a synchronization point immediately prior to when the backup was made.

#1

• When the updatable mode is specified, the RDAREAs to be backed up must have been created in a character special file; an RDAREA created in a regular file cannot be backed up in the updatable mode.
• Do not make a backup in the updatable mode during execution of a UAP (including utilities) in the no-log mode or pre-update log acquisition mode.
• To execute the pdcopy command in the updatable mode when the Logical Volume Manager (LVM) is used for the database, the target RDAREAs must be backed up and held. For details on backup-hold, see 6.7 Backup acquisition using backup-hold (backup without using the pdcopy command).

#2

The run ID and generation number of the system log file needed to recover the RDAREA are output to the database copy utility's processing results output file.

Notes

A backup made after an RDAREA structure change must be made in one of the following backup acquisition modes:

• Referencing/updating-impossible mode (x)
• Referencing-permitted mode (r)

The backup acquisition mode that can be specified for backup processing depends on the database update log acquisition mode, as shown in the table below. For details on the database update log acquisition mode, see 7. Operation Without Acquiring a Database Update Log.

Table 6-2 Backup acquisition mode depending on the database update log acquisition mode

Database update log acquisition mode	Specifiable backup acquisition mode (-M option specification)
Log acquisition mode	Referencing/updating-impossible mode (x) Referencing-permitted mode (r) Updatable mode (s)
Pre-update log acquisition mode	Referencing/updating-impossible mode (x) Referencing-permitted mode (r)
No-log mode

Notes

1. Do not make a backup in the updatable mode (-M s specification) during execution of a UAP (including utilities) in the no-log mode or pre-update log acquisition mode.
2. After execution of a UAP (including utilities) in the no-log mode or pre-update log acquisition mode, make the backup in one of the following modes:

• Referencing/updating-impossible mode (-M x specification)
• Referencing-permitted mode (-M r specification)