单项选择题
A. The optimizer used a dynamic plan for the query.
B. The optimizer chose different plans because automatic dynamic sampling was enabled.
C. The optimizer used re-optimization cardinality feedback for the query.
D. The optimizer chose different plan because extended statistics were created for the columns used.
多项选择题 You notice a performance change in your production Oracle database and you want to know which change has made this performance difference. You generate the Compare Period Automatic Database Diagnostic Monitor (ADDM) report to further investigation. Which three findings would you get from the report?（）
单项选择题 Examine the following query output: You issue the following command to import tables into the hr schema: $ > impdp hr/hr directory = dumpdir dumpfile = hr_new.dmp schemas=hr TRANSFORM=DISABLE_ARCHIVE_LOGGING: Y Which statement is true?（）
多项选择题 An administrator account is granted the CREATE SESSION and SET CONTAINER system privileges. A multitenant container database (CDB) instant has the following parameter set: THREADED_EXECUTION = FALSE Which four statements are true about this administrator establishing connections to root in a CDB that has been opened in read only mode?（）