Oracle数据表被drop后的恢复
Oracle数据表对于被drop的表和索引,都会存放在回收站中(所以对于生产的数据库必须设置好回收站功能),因为本次生成环境在drop掉
Oracle数据表对于被drop的表和索引,都会存放在回收站中(所以对于生产的数据库必须设置好回收站功能)
因为本次生成环境在drop掉已有的表后,重新创建了许多的表,所有直接还原的话会提示原有对象存在,表名重复。其中解决方法是:先重命名已经存在的表名,让后还原删除的表,最后进行数据合并
1 重命名已经存在的表
spool bak.txt
select 'alter table '||t.original_name||' rename to '||t.original_name||'_bak;',' select count(*) from '||t.original_name||'_bak;' from user_recyclebin t;
spool off
那么会把修改表名的语句存放在bak.txt中,我们可以稍微调整一下直接运行这个脚本或者是拷贝的sqlplus中执行也可以
因为考虑到数据的合并,对于 count(*)大于0 的数据需要进行数据的合并,否则可以不用管它
2 使用还原数据库的命令进行数据还原
spool bak2.txt
select ' flashback table '||t.original_name|| ' to before drop' from user_recyclebin t;
spool off
执行这个bak2.txt中保存的脚本,可以进行数据的还原
3 进行数据库中表数据的合并()
需要注意的有的数据是直接insert to 就可以,但是有的本来是计时器的功能,只需要对数量进行累加就可以,,还有的数据时因为没有重建了一份一样的数据,对于这样的数据就不需要管他
4 重建索引
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本文永久更新链接地址:

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