flashback query闪回查询

闪回查询是使用undo数据查询过去某个时间点表中数据，一定程度上可以恢复误操作。主要是DML操作

SQL> select count(*) from hr.tb2;  COUNT(*)----------        19SQL> select current_scn from v$database;CURRENT_SCN-----------    3187961SQL> delete from hr.tb2 where rownum<11;10 rows deleted.SQL> commit;Commit complete.SQL> select count(*) from hr.tb2;  COUNT(*)----------         9SQL> select count(*) from hr.tb2 as of scn 3187961;  COUNT(*)----------        19

恢复数据

SQL> delete from hr.tb2;9 rows deleted.SQL> commit;Commit complete.SQL> insert into hr.tb2 select * from hr.tb2 as of scn 3187961;19 rows created.SQL> commit;Commit complete.

实际生产库操作复杂多，变化快，SCN变化也快，那么可借助于logminer工具。