单项选择题
A. EXECUTE DBMS_SCHEDULER.PURGE_LOG（log_history => 5， job_name => ’JOB1’）；
B. EXECUTE DBMS_SCHEDULER.PURGE_LOG（ log_history => 5， job_name => ’JOB_LOG’）；
C. EXECUTE DBMS_SCHEDULER.PURGE_LOG（ log_history => 5， which_log => ’JOB1’）；
D. EXECUTE DBMS_SCHEDULER.PURGE_LOG（ log_history => 5， which_log =>’JOB_LOG’）；
单项选择题 Yoursystemperformsheavytransactionprocessingbetween8：00A.M.and5：00P.M.butrunsbatchprocessingandreportsafterthat.Youdecidetocreateaseparateresourceplantogovernresourceallocationforeachtimeperiod.Whichschedulerobjectwillyouusetoswitchautomaticallybetweenthetworesourceplans？（）
单项选择题 You executed the following code： BEGIN DBMS_SCHEDULER.SET_ATTRIBUTE （ NAME => ’JOB_A’， ATTRIBUTE => ’JOB_PRIORITY’， VALUE => 7）； END； / After analyzing the above code， what conclusion will you draw？（）
单项选择题 Williamiscreatingajobclass.WilliamspecifiestheLOGGING_FULLsettingfortheLOGGING_LEVELattributeatthetimeofjobclasscreation.Whatistheimpactofusingthissetting？（）