Tablespace Point-in-Time Recovery--关于表空间即时点恢复

文档地址：http://docs.oracle.com/cd/B19306_01/server.102/b14220/backrec.htm#i1012545
Tablespace Point-in-Time Recovery--表空间即时点恢复
The tablespace point-in-time recovery(TSPITR) feature lets you recover one or more tablespaces to apoint in time that is different from the rest of thedatabase.

--表空间即时点恢复特征让你恢复一个或者多个表空间到一个时间点上，而且这个时间点不同于数据库其余部分的时间点。

TSPITR is most useful when you want to:

Recover from an erroneous drop or truncate tableoperation

--译文：从一个错误删除或者删除表操作。

Recover a table that has become logically corrupted

Recover from an incorrect batch job or other DML statement thathas affected only a subset of the database

Recover one independent schema to a point different from therest of a physical database (in cases where there are multipleindependent schemas in separate tablespaces of one physicaldatabase)

Recover a tablespace on a very large database (VLDB) rather thanrestore the whole database from a backup and perform a completedatabase roll-forward

TSPITR has the followinglimitations:---TSPITR的限制

You cannot use it on the

SYSTEM

tablespace,an UNDO tablespace, or any tablespace that contains rollbacksegments.

---你不能将其应用到SYSTEM表空间和UNDO表空间，或者任何包括回滚段的表空间上。

Tablespaces that contain interdependent data must berecovered together.

--包含相互依赖数据的多个表空间必须被一起同时恢复。例如：你要即时恢复拥有索引的表空间的话，必须和索引所引用的基表所在的表空间一起同时做即时点恢复。

For example, if two tables are in separatetablespaces and have a foreign key relationship, then bothtablespaces must be recovered at the same time; you cannot recoverjust one of them. Oracle can enforce this limitation when itdetects data relationships
that have been explicitly declared withdatabase constraints. There could be other data relationships thatare not declared with database constraints. Oracle cannot detectthese, and the DBA must be careful to always restore a consistentset of tablespaces.

注意：恢复集表空间必须为自包含；

违反自包含表空间集合的常见情况如下：

1> 表空间集合包含有SYS 方案对象

2>表空间集合包含了索引所在的表空间，但没有包含索引基表所在的表空间

3>表空间集合没有包含分区表的所有分区

4> 表空间集合包含了表所在的表空间，但没有包含其LOB 列所在的表空间

检查自包含方式：

SQL> connect sys/oracle@demo as sysdba

SQL> executedbms_tts.transport_set_check('user01',true);

SQL> Select * From transport_set_violations;