Storage considerations for recovery

When deciding which recovery method to use, consider the storage space required.

The version recovery method requires space to hold the backup copy of the database and the restored database. The rollforward recovery method requires space to hold the backup copy of the database or table spaces, the restored database, and the archived database logs.

If a table contains long field or large object (LOB) columns, you should consider placing this data into a separate table space. This will affect your storage space considerations, as well as affect your plan for recovery. With a separate table space for long field and LOB data, and knowing the time required to back up long field and LOB data, you might decide to use a recovery plan that only occasionally saves a backup of this table space. You can also choose, when creating or altering a table to include LOB columns, not to log changes to those columns. This will reduce the size of the required log space and the corresponding log archive space.

To prevent media failure from destroying a database and your ability to restore it, keep the database backup, the database logs, and the database itself on different devices. For this reason, it is highly recommended that you use the newlogpath configuration parameter to put database logs on a separate device once the database is created.