多项选择题
A.Speeds up subsequent media recover actions.
B.Writes any uncorrupted block to disk during the test recovery.
C.Can be invoked by adding the TEST option to any RECOVER command.
D.Allows the Administrator to determine how many blocks are affected by corruption.
E.Marks blocks as corrupt in memory， allowing the test recover to proceed to completion.
多项选择题 Examine the code： CREATE ROLE readonly IDENTIFIES USING app.chk_readwrite ； CREATE ROLE readwrite IDENTIFIED USING app.chk_readwrite ； CREATE OR REPLACE PROCEDURE app.chk_readwrite AUTHID CURRENT_USER IS ipchk STRING（30）； BEGIN IF sys_context（‘USERENV’，’ISDBA’）=’TRUE’ THEN DBMS_SESSION.SET_ROLE‘READWRITE’） ； ELSE DBMS_SESSION.SET_ROLE（‘READONLY’） ； END； / Which three statements correctly describe the Secure Application role definition？（）
单项选择题 Consider this RMAN command： RMAN> CONFIGURE RETENTION POLICY CLEAR； What is the effect of this command？（）
单项选择题 Examine the command： ALTER DATABASE ADD SUPPLEMENTAL LOG DATA （PRIMARY KEY） COLUMNS； What does the command accomplish？（）