---

What is an obsolete backup set？（）  
A: A backup set that is missing one or more backup set pieces
B: A backup that has exceeded the retention criteria and is no longer needed
C: A backup set that does not include archived redo logs
D: A backup set that can not be recovered due to corruption
E: A backup set superceded by a datafile copy

---

出自：Oracle认证

显示答案