单项选择题 You have lost all your SYSTEM tablespace datafiles （system_01.dbf and system_02.dbf） nd the database has crashed.  What would be the appropriate order of operations to correct the situation？（）   a. Mount the database with the startup mount command.  b. Take the SYSTEM datafile offline with the alter database command.  c. Restore the SYSTEM_01.dbf datafile from backup media with the required archived redo logs.  d. Restore all SYSTEM tablespace-related datafiles from backup media. e. Issue the recover tablespace SYSTEM command.  f. Issue the recover datafile SYSTEM_01.dbf command.  g. Open the database with the alter database open command.  h. Open the database with the alter database open resetlogs command.

单项选择题 Assoonasyoudiscoverthatyouhavelostanonlineredolog，ifthedatabaseisstillfunctioning，whatshouldbeyourfirstaction？（）

单项选择题 Your database has experienced a loss of datafile users_01.dbf， which is associated with a ablespace called USERS.  The database is still running.  Which answer properly describes the rder of the steps that you would use to recover from this error？（）   a. Shut down the database.  b. Take the users_01.dbf datafile offline with the alter database command.  c. Restore the users_01.dbf datafile from backup media with the required archived redo logs.  d. Restore all users tablespace-related datafiles from backup media. e. Issue the recover tablespace users command. f. Issue the recover datafile users_01.dbf command. g. Start up the database.  h. Bring the users_01.dbf datafile online with the alter database command.