Incremental backups are database backups that save only
the data that changed since the last backup. Because the system copies
a small subset of the data, incremental backups require less time
to complete than full backups. Use incremental backups to keep your
backups current and reduce the frequency of time-consuming full backups.
IBM® Netezza® supports
two types of incremental backups:
Differential
Includes all the changes that are made to the database since the
previous backup (full, differential, or cumulative).
Cumulative
Includes all the changes that are made to the database since the
last full backup. Cumulative backups incorporate and replace any differential
backups that were run since the last full backup.
Use cumulative
backups to consolidate differential backups so that if you must restore
data, the restoration requires fewer steps and less media.
The following figure shows sample backups, beginning with a full
backup (shown as the letter A), then a series of differential (C)
and cumulative (B) backups.Figure 1. Database
backups timeline
The backups in the previous figure comprise a backup set, which
is a collection of backups that are written to a single location that
consists of one full backup and any number of incremental backups.
