Which SAP HANA backup type should you use, and when
The three things HANA backs up
SAP HANA separates what it protects into data and logs, and that distinction drives every recovery decision you will be asked about.
- Complete data backup: a full copy of the persistent data at a point in time. It is the baseline everything else is measured against.
- Delta backup: only what changed since a previous backup. Incremental measures from the last delta, differential measures from the last complete data backup.
- Log backup: a continuous stream of redo log segments, written automatically on an interval or when a segment fills.
Why a data backup on its own is not enough
Restoring only a data backup returns the database to the instant that backup finished. Everything committed afterwards is gone. That is acceptable for refreshing a sandbox and unacceptable for production.
Point-in-time recovery closes the gap. HANA replays log backups on top of the restored data backup until it reaches the moment you asked for. If log backups are missing, the recovery stops where the logs stop.
Where each type earns its keep
Complete data backups are simple to reason about and slow to take. Delta backups shorten the nightly window at the cost of a longer recovery chain, because recovery has to apply the baseline and then each delta in order.
Differential backups keep that chain short: baseline, one differential, then logs. Incremental backups keep each individual backup smallest but make the chain longest. The trade is backup time against recovery time, and which one matters is a business question rather than a technical one.
The traps worth memorising
Questions in this area tend to test the same handful of behaviours rather than obscure syntax.
- Log backups run automatically once log backup is enabled. They are not scheduled per night alongside the data backup.
- Recovery always starts from a data backup. There is no way to recover from log backups alone.
- An incremental chain is only as good as its weakest link. One missing delta breaks recovery from that point forward.
Common questions
- Can you recover SAP HANA to a specific point in time?
- Yes, provided you have a data backup taken before that point and an unbroken set of log backups covering the interval between the two. Recovery restores the data backup and then replays the logs up to the timestamp you specify.
- What is the difference between an incremental and a differential HANA backup?
- An incremental backup contains changes since the previous backup of any kind, so recovery must apply every incremental in sequence. A differential backup contains changes since the last complete data backup, so recovery applies the baseline and one differential.
- Do log backups replace data backups?
- No. Log backups only describe changes. Without a data backup to apply them to, they cannot rebuild the database.