Flashback
Flashback query(undo)
select * from table_name as of timestamp
to_timestamp(‘2008-03-03 12:00:00‘,‘yyyy-mm-dd hh24:mi:ss‘); select * from table_name as of scn 123456;
Flashback table(undo,恢复表到某时间点，阻塞写操作) --必须开启行移动
alter table table_name enable row movement; flashback table table_name to timestamp(JUL-07-2008,02:33:00); flashback table table_name to scn 123456;
flashback table table_name to timestamp ‘2008-03-03 12:05:00‘ enable triggers; --只恢复trigger或index状态，不恢复更改
Flashback drop(recyclebin) --管理recyclebin show recyclebin;
select * from user_recyclebin; select * from dba_recyclebin; purge recyclebin; --闪回drop表
flashback table table_name to before drop [rename to new_name];
--recyclebin中有同名，闪回最近删除的；闪回后有同名表，需rename
Flashback database(flashback log,redo log,archive log) --开启flashback database shutdown immediate startup mount
alter database flashback on --必须先开启归档
--闪回数据库(mount状态,read only方式检查,resetlogs方式打开) flashback database to time to_date(xxx);
flashback database to time to_timestamp(xxx); flashback database to scn xxx;
flashback database to sequence xxx thread 1; flashback database to timestamp(sysdate-1/24); --管理闪回区
db_recovery_file_dest --闪回区路径 db_recovery_file_dest_size --闪回区大小 db_flashback_retention_target --闪回数据保存时间
select * from v$flash_recovery_area_usage; --闪回区使用率
select * from v$flashback_database_log; --闪回区情况，如能恢复到的最早的时间点
Flashback version query(undo)
--查询表的多个版本，记录行的改变
select versions_starttime,versions_endtime,versions_startscn,versions_endscn, versions_xid,versions_operation,a,b
from test versions between timestamp minvalue and maxvalue order by versions_starttime;
Flashback transaction query(undo) --查看当前事务号
select xid from v$transaction; --查看undo_sql
select undo_sql from flashback_transaction_query
where xid =hextoraw(‘xxxxxxx‘); --不使用hextoraw很难利用系统的索引