单项选择题
A. ALTER DISKGROUP data CHECK;
B. ALTER DISKGROUP data CHECK DISK;
C. ALTER DISKGROUP data CHECK FILE;
D. ALTER DISKGROUP data CHECK DISK IN FAILURE GROUP 1;
多项选择题 Which two statements are correct about database transportation? （）
多项选择题 Which two statements are true with respect to the maintenance window? （）
多项选择题 You are using the flash recovery area (fast recovery area in 11g Release 2) to store backup related files in your database. After regular monitoring of space usage in the Mash recovery area. You realize that the flash recovery area is jetting filled up very fast and it is running out of space. Your database flash recovery area is low on space and you have no more room on disk. Proactively, which two options could you use to make more space available in the flash recovery？（）
