单项选择题
A.A leaf will be marked as invalid.
B.An update in a leaf row takes place.
C.The index will be updated automatically at commit.
D.A leaf row in the index will be deleted and inserted.
E.The index becomes invalid when you make any updates
多项选择题 YouworkasadatabaseadministratorforCertkiller.com.YouhavesettheretentionperiodforAutomaticRepository（AWR）statisticstofourdaysandcollectionintervalto15minutes.YouwanttoviewthestatisticscollectedandstoredinAWRsnapshot.WhichtwomethodswouldyouusetoviewtheAWRstatistics？（）
单项选择题 You are working on the Certkiller database. What is the default name of the alert log file in this database？（）
单项选择题 YouworkasadatabaseadministratorforCertkiller.com.Inaproductionenvironment，userscomplainabouttheslowresponsetimewhenaccessingthedatabase.YouhavenotoptimizedthememoryusageoftheOracleinstanceandyoususpecttheproblemtobewiththememory.Towhichtypeofobjectwouldyourefertodeterminethecauseoftheslowresponse？（）