单项选择题 You are connecting to an Oracle database server from a client by using the following connect string：  SQL> CONNECT hr/hr@pdserver.us.oracle.com：1521/proddb  Which naming method is being used in this case？（）

单项选择题 The Automatic Database Diagnostic Monitor （ADDM） analysis runs every 60 minutes on your database. Your database if facing a series of interrelated problems over a period of two hours. You need to ensure that the ADDM analysis is run over a time span of two hours in future. What would you do？（）

多项选择题 You want to enforce a company’s business policy on several objects by using a singlepolicy function.  Which two types of policies can be assigned to the policy_type argument in the dbms_rls.add_policy procedure to achieve the above objective？（）