单项选择题
A. The backup is deleted.
B. The backup is marked unavailable.
C. The backup overrides the backup retention policy.
D. the backup becomes eligible for deletion according to the existing retention policy.
单项选择题 WhichstatementdescribestheinformationreturnedbytheDBMS_SPACE.SPACE_USAGEprocedureforLOBspaceusage？（）
单项选择题 WhichstatementistrueregardingonlineredefinitionforthemigrationofBasicFileLOBstoSecureFileLOBs？（）
单项选择题 ou need to configure fine-grained access control to external network resources from within your database. You create an access control list （ACL） using the DBMS_NETWORK_ACL_ADMIN package. Which statement is true regarding the ACL created？（）