Db+file+sequential+read

数据库等待事件Dbfilesequentialread的介绍。ThedbfilesequentialreadOraclemetriceventsignifiesthattheuserprocessisreadingbuffersintotheSGAbuffercacheandiswaitingforaphysicalI/Ocalltoreturn.Thiscalldiffersfromascatteredread,becauseasequentialreadisreadingdataintocontiguousmemoryspace.Asequenti