Database considerations for save and restore
Consider these tips when using the i5/OS® database save and restore functions.
- When you save an object to a save file, you can prevent the system from updating the date and time of the save operation by specifying UPDHST(*NO)
on the save command.
- When you restore an object, the system always updates the object description with the date and time of the restore operation. Display the object description and other save/restore related information by using the Display Object Description (DSPOBJD) command with DETAIL(*FULL).
- To display the objects in a save file, use the Display Save File (DSPSAVF)
command.
- To display the objects on the media, specify DATA(SAVRST) on the Display Diskette (DSPDKT) or Display Tape (DSPTAP) command.
- To display the last save/restore date for a database file, type: DSPFD FILE(file-name) TYPE(*MBR).
Also consider automatically writing records to auxiliary storage.
Force-writing data to auxiliary storage
The force-write ratio (FRCRATIO) parameter on the create file and override database file commands indicates how often the records are to be written to auxiliary storage.
A force-write ratio of one immediately writes every add, update, and delete request to auxiliary storage for the file in question. However, choosing this option can reduce system performance. Therefore, consider saving your files and journaling your files as the primary methods for protecting database files.
Parent topic:
Recovering and restoring your database
Related concepts
Backup and Recovery PDF
Backup and recovery
Related reference
Display Object Description (DSPOBJD) command
Display Save File (DSPSAVF) command
Display Tape (DSPTAP) command