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Which two statements are true about the Automatic Workload Repository （AWR）（） All AWR tables belong to the SYSTEM schema.。 The AWR contains systemwide tracing and logging information.。 The snapshots collected by the AWR are accessible through data dictionary views.。 The snapshots collected by the AWR are used by self-tuning components in the database.。
在进行变压器的空载试验和负载试验时，若试验频率偏差较大，则下列参数中与频率无关的是（）。 空载损耗。 空载电流。 绕组的电阻损耗。 绕组的涡流损耗。 由漏磁通引起的构件涡流损耗。 阻抗电压的有功分量。 阻抗电压的无功分量。
Your database operates in ARCHIVELOGmode. The redo log files are not multiplexed and one of the online redo logs is missing. The missing redo log sequence， 230， is not archived and it contained information from 10：35 a.m. onwards. The current time is 11：00 a.m. Because of a disk crash， you executed the following command to perform an incomplete recovery： RMAN> RUN { 2> SET UNTIL SEQUENCE 230 THREAD 1； 3> ALTER DATABASE MOUNT； 4> RESTORE DATABASE； 5> RECOVER DATABASE； 6> ALTER DATABASE OPEN RESETLOGS； 7> }； With reference to this scenario， which statement is true？（） RMAN recovers up to log sequence 230， but not including 230.。 RMAN returns an error because the log sequence number mentioned in the command should be 229.。 RMAN returns an error because the log sequence number mentioned in the command may never be missing.。 RMAN recovers up to and including log sequence 229 but then returns an error because log sequence 230 is missing.。
正常生产情况下稳定区轻油产品的进罐前压力应控制在（） 越高越好。 0.4MPa左右。 越低越好。
You work as a database administrator for Certkiller .com. In the Certkiller PRODUCTION database you have granted RESUMABLE system privilege to the CONNECT role.Resumablespace operation has been enabled for all user session. You want users NOT to be aware of any kind of space-related problems while performing transactions. Instead， you want the problem to be resolved by a database trigger automatically. Which combination of triggering time and event would you use to achieve this objective？（）
