28、Which two are true about external tables?
A. They support the ORACLE_DATAPUMP access driver.
B. They have extents.
C. They support all DML operations.
D. They can always be updated using SQL.
E. They can be stored in an ASM Cluster File System (ACFS).
Correct Answer: AE
原文：https://www.cnblogs.com/cnblogs5359/p/9395078.html