多项选择题
A. BACKUP PLUGGABLE DATABASE PDB1 while connected to the root container
B. BACKUP PLUGGABLE DATABASE PDB1 while connected to the PDB1 container
C. BACKUP DATABASE while connected to the PDB1 container
D. BACKUP DATABASE while connected to the boot container
E. BACKUP PLUGGABLE database PDB1 while connected to PDB2
多项选择题 On your Oracle 12c database, you Issue the following commands to create indexes SQL > CREATE INDEX oe.ord_customer_ix1 ON oe.orders (customers_id, sales_rep_id) INVISIBLE; SQL> CREATE BITMAP INDEX oe.ord_customer_ix2 ON oe.orders (customers_id, sales_rep_id); Which two statement are correct?（）
单项选择题 A database is stored in an Automatic Storage Management (ASM) disk group, disk group, DGROUP1 with SQL: There is enough free space in the disk group for mirroring to be done. What happens if the CONTROLLER1 failure group becomes unavailable due to error of for maintenance?（）
多项选择题 Which two are prerequisites for performing a flashback transaction?（）