Youhavelostallyouronlineredologs.Asaresult，yourdatabasehascrashed.Youhavetriedtorestartthedatabaseandcleartheonlineredologfiles，butwhenyoutrytoopenthedatabaseyougetthefollowingerror.SQL>startupORACLEinstancestarted.TotalSystemGlobalArea167395328bytesFixed

Youhavelostallyouronlineredologs.Asaresult，yourdatabasehascrashed.Youhavetriedtorestartthedatabaseandcleartheonlineredologfiles，butwhenyoutrytoopenthedatabaseyougetthefollowingerror.

SQL>startupORACLEinstancestarted.

TotalSystemGlobalArea167395328bytesFixedSize1298612bytesVariableSize142610252bytesDatabaseBuffers20971520bytesRedoBuffers2514944bytesDatabasemounted.

ORA-00313：openfailedformembersofloggroup2ofthread1ORA-00312：onlinelog2thread1：，，/oracle01/oradata/orcl/redo02a.logORA-27037：unabletoobtainfilestatusLinuxError：2：NosuchfileordirectoryAdditionalinformation：3

ORA-00312：onlinelog2thread1：，，/oracle01/oradata/orcl/redo02.logORA-27037：unabletoobtainfilestatusLinuxError：2：NosuchfileordirectoryAdditionalinformation：3

SQL>alterdatabaseclearlogfilegroup2；alterdatabaseclearlogfilegroup2*ERRORatline1：

ORA-01624：log2neededforcrashrecoveryofinstanceorcl（thread1）ORA-00312：onlinelog2thread1：，，/oracle01/oradata/orcl/redo02.logORA-00312：onlinelog2thread1：，，/oracle01/oradata/orcl/redo02a.log

Whatstepsmustyoutaketoresolvetheerror？（）

a.Issuetherecoverdatabaseredologscommand.

b.IssuetheStartupMountcommandtomountthedatabase.

c.Restorethelastfulldatabasebackup.

d.Performapoint-in-timerecovery，applyingallarchivedredologsthatareavailable.

e.Restoreallarchivedredologsgeneratedduringandafterthelastfulldatabasebackup.

f.Openthedatabaseusingthealterdatabaseopenresetlogscommand.

g.Issuethealterdatabaseopencommand.