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Oracle 10g闪回总结

Jun 07, 2016 pm 05:26 PM

Oracle 10g闪回总结 1.flashback query (undo) select current_scn from v$database; select * from t as of scn scn号;

Oracle 10g闪回总结
 
1.flashback query (undo) 
select current_scn from v$database;
 select * from t as of scn scn号;   
时间与scn转换函数:
 scn_to_timestamp()
 to_timestamp()
 timestamp_to_scn()
 
2.flashback table(undo)
 select row_movement from dba_tables where table_name='T' and owner='TEST';
 alter table t enable row movement;
 flashback table t  to scn scn号;
 
3.flashback versions query(undo)
 select * from t versions between scn minvalue and maxvlaue
 order by versions_startscn;
 
4.flashback transaction query(undo)
 select * from flashback_transaction_query where xid='事务id';
 事务id对应到flashback versions query中的versions_xid,这样可以找到undo_sql,对误操作撤消。
 
5.flashback drop
 drop table t;
 show recyclebin
 select * from dba_recyclebin;
 flashback table t to before drop;
 select * from dba_indexes where table_name='T';
 如果有索引,索引同样会被闪回,但是索引名称会发生变化,使用
 alter index old_index_name rename to new_index_name;更改索引名称。
t表上的触发器也同样如些。
 
彻底删除表
 drop table t purge;
 清回收站
 purge recyclebin; 

是否启用recyclebin
 show parameter recyclebin;

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