v$session_wait 用来查询redo buffer的空间信息 select sid,event,seconds_in_wait,state from v$session_wait where event = 'log buffer space'; v$sysstat redo buffer空间分配的重试次数及redo的数量 redo entries select name,value from v$sysstat where name in ('redo entries','redo…
61. You are working in an online transaction processing (OLTP) environment. You realize that the salary for an employee, John, has been accidentally modified in the EMPLOYEES table. Two days ago, the data was in the correct state. Flashback logs gene…