Henry Xie 's blog

Sometimes alert log of DB is too large.  We may mv , rm  or vi them to make it smaller However it may affect format the alert logs, adrci  ...

2 possible reasons check password file, if possible, recreate them on all nodes to make them consistent double check password file name ,...

Sometimes we need to know date and redo log sequence from SCN When we debug, we know SCN, then we need to know what archive logs and log se...

Use DBA_HIST_ACTIVE_SESS_HISTORY: To get client machine name: SELECT distinct machine  FROM DBA_HIST_ACTIVE_SESS_HISTORY To get timefra...

sometimes we clean recovery area manually , delete archive logs, old files ourselves the output v$flash_recovery_area_usage can be  incorre...