Complete recovery is recovering a database to the most recent point in time, without
the loss of any committed transactions. Generally, the term "recovery" refers to
complete recovery.
完全还原是还原数据库到最近的时间点,没有丢失任何提交的事务。简而言之,词语“还原”
也就是完全还原。
Occasionally, however, you need to return a database to its state at a past point in time.
For example, to undo the effect of a user error, such as dropping or deleting the
contents of a table, you may want to return the database to its contents before the
delete occurred. In incomplete recovery, also known as point-in-time recovery, the
goal is to restore the database to its state at some previous target SCN or time.
有时,你需要将数据库返回到过去的一个时间点。比如,回滚一个用户错误的影响,
比如DELETE或者DROP表的内容,你想返回到数据库被DELETE之前的内容。在不完全
还原中,众所周知的时间点还原,目标是修复数据库到它之前目标SCN或者时间的状态。
Point-in-time recovery is one possible response to a data loss caused by, for instance, a
user error or logical corruption that goes unnoticed for some time.
时间点的还原可能是一个数据丢失所造成的反应,对于实例,一个用户的错误或者是逻辑
损坏在一段时间内容是被忽视的。
Point-in-time recovery is also your only option if you have to perform a recovery and
discover that you are missing an archived log covering time between the backup you
are restoring from and the target SCN for the recovery. Without the missing log, you
have no record of the updates to your datafiles during that period. Your only choice is
to recover the database from the point in time of the restored backup, as far as the
unbroken series of archived logs permits, then perform an OPEN RESETLOGS and
abandon all changes in or after the missing log. (If you discover that you have lost
archived logs and your database is still up, you should do a full backup immediately.)
时间点的还原也可能是你唯一的选项如果你执行一个还原并且发现你丢失了在介于你使用
来修复的备份和对于还原的目标SCN之间。没有了丢失的日志,你没有在那个阶段更新数据库
的记录,你唯一的选择是还原数据库从用于修复的备份中,当一系列归档日志许可时候,那么
执行OPEN RESETLOGS并且放弃所有改变在丢失日志或者丢失之后。(如果你发现你已经丢失了
归档日志并且你的数据库仍然在运行,你应当马上执行一个全备份)
Note: If only one tablespace is affected by the data loss, you have
the option of performing point-in-time recovery on that tablespace
instead of the entire database. Tablespace point-in-time recovery
(often abbreviated TSPITR) is an advanced technique documented
in Oracle Database Backup and Recovery Advanced User's Guide.
备注:如果仅一个表空间受影响针对数据丢失,你可以选择执行基于时间点的还原表空间去代替整个
整个数据库的还原。表空间基于时间点的还原(通称简写为TSPITR)是一个高级的技术,可见于文件档
Oracle Database Backup and Recovery Advanced User's Guide.