Question
A DBA is reviewing the following logs to determine the current data backup plan for a primary data server:
| Timestamp | Activity | Size | Duration |
|---|---|---|---|
| 2023-Jan-23 23:59:00 | Back up to disk | 7.35GB | 03:14:55 |
| 2023-Jan-24 23:59:00 | Back up to disk | 0.12GB | 00:14:22 |
| 2023-Jan-25 23:59:00 | Back up to disk | 1.11GB | 01:11:55 |
| 2023-Jan-26 23:59:00 | Back up to disk | 1.23GB | 01:22:12 |
| 2023-Jan-27 23:59:00 | Back up to disk | 1.22GB | 01:19:56 |
| 2023-Jan-28 23:59:00 | Back up to disk | 1.21GB | 01:17:19 |
| 2023-Jan-29 23:59:00 | Back up to disk | 0.94GB | 01:01:29 |
| 2023-Jan-30 23:59:00 | Back up to disk | 8.1GB | 03:45:66 |
Which of the following best describes this backup plan?
- A. Monthly full, daily differential
- B. Daily differential
- C. Daily full
- D. Weekly full, daily incremental Correct
Explanation
A large backup runs on January 23 and again seven days later on January 30, which marks a weekly full backup. The daily backups in between are small and do not keep growing (1.23GB, 1.22GB, 1.21GB, 0.94GB), so each one captures only the changes since the previous backup: that is incremental. Differential backups would grow every day because each contains all changes since the last full backup, and daily full backups would all be about the size of the full ones.
