内源性污染
You are managing the APPPROD database as a DBA. You plan to duplicate this database in the same system with the name DUPDB. You issued the following RMAN commands to create a duplicate database: Which three are the prerequisites for the successful execution of the above command?（） [" The source database should be open"," The target database should be in ARCHIVELOG mode if it is open"," RMAN should be connected to both the instances as SYSDBA"," The target database backups should be copied to the source database backup directories"," The password file must exist for the source database and have the same SYS user password as the target"]
化工设备图中，表示点焊的焊接焊缝是（）。 ["○","∪","Δ","⊿"]
《统一商法典》第4A编规定的解决支付命令的认证与欺诈损失的分担问题的机制称为（） ["安全程序","分担机制","认证程序","监测机制"]
You work as a database administrator for Supportcenter.cn. One of the user sessions was terminated abnormally in the middle of a transaction. What does Oracle database do to recover it？（） ["Uses undo data for roll forward","Uses Flashback Log for recovery","Uses online redo logs to roll back","Uses undo data to roll back the transaction","Uses Recovery Manager （RMAN） to roll back","Uses the System Monitor （SMON） background process to perform instance recovery"]
排球拦网技术的全过程是由：（）、（）、（）、（）和（）五环节组成。
