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flashback drop 误删除的表后的恢复及对回收站中表的操作

1.误删除表,使用flashback drop功能找回

SQL> select * from tab;

TNAME                          TABTYPE  CLUSTERID

------------------------------ ------- ----------

TEST                           TABLE

SQL> select * from test;

         A

----------

         1

         2

         3

         4

         5

         6

         7

         8

         0.

SQL> show parameter recyclebin;    -验证回收站是否打开--如未打开不能使用闪回DROP--11G默认打开

NAME                                 TYPE        VALUE

------------------------------------ ----------- ------------------------------

recyclebin                           string      on

SQL> show recyclebin;

SQL> drop table test;

Table dropped.

查询回收站,删除的表在里面,并被系统自己命令--BIN$开头一长串---从ORIGINAL NAME 列可以看到表的原名是test

SQL> show recyclebin;

ORIGINAL NAME    RECYCLEBIN NAME                OBJECT TYPE   DROP TIME

---------------- ------------------------------ ------------ -------------------

TEST             BIN$387tHPzSqO/gQKjA3QEnzg==$0 TABLE        2013-06-23:17:29:01

SQL> select * from tab;

TNAME                          TABTYPE  CLUSTERID

------------------------------ ------- ----------

BIN$387tHPzSqO/gQKjA3QEnzg==$0 TABLE

使用回收站中的BIN$的表名也能查询到表中数据

SQL> select * from "BIN$387tHPzSqO/gQKjA3QEnzg==$0";

         A

----------

         1

         2

         3

         4

         5

         6

         7

         8

执行闪回删除表的命令并查询数据是否完整:

SQL> flashback table test to before drop;

Flashback complete.

SQL> select * from "BIN$387tHPzSqO/gQKjA3QEnzg==$0";

select * from "BIN$387tHPzSqO/gQKjA3QEnzg==$0"

              *

ERROR at line 1:

ORA-00942: table or view does not exist

SQL> select * from tab;

TNAME                          TABTYPE  CLUSTERID

------------------------------ ------- ----------

TEST                           TABLE

SQL> select * from test;

         A

----------

         1

         2

         3

         4

         5

         6

         7

         8

2.闪回删除并将表重命名

[email protected]>select * from test5;

        ID NAME

---------- ----------

         2 b       

[email protected]>drop table test5;

Table dropped.

[email protected]>flashback table test5 to before drop rename to test6;

Flashback complete.

[email protected]>select * from test6;

        ID NAME

---------- ----------

         2 b

3.回收站内查看删除的表,单个删除回收站里的表、全部清空回收站。

SQL> create table test2 as select * fromtest1;

表已创建。

SQL> insert into test2values('00002','baishan2');

已创建 1 行。

SQL> select * from test2;

ID   NAME

----- ----------

00001 baishan

00002 baishan2

SQL> show recyclebin

SQL> drop table test1;

表已删除。

删除表后查看回收站里,可以看到删除的表名,及删除时间

SQL> showrecyclebin

ORIGINAL NAME    RECYCLEBIN NAME                OBJECT TYPE  DROP TIME

---------------------------------------------- ------------ -------------------

TEST1            BIN$kUfBJ3qcTSiLxqU6hmoEcw==$0TABLE        2013-02-10:12:17:11

SQL> select * from cat;

TABLE_NAME                     TABLE_TYPE

------------------------------ -----------

BIN$kUfBJ3qcTSiLxqU6hmoEcw==$0 TABLE

TEST                           TABLE

TEST2                          TABLE

SQL> create table test3 as select * fromtest2;

表已创建。

SQL> select * from cat;

TABLE_NAME                     TABLE_TYPE

------------------------------ -----------

BIN$kUfBJ3qcTSiLxqU6hmoEcw==$0 TABLE

TEST                           TABLE

TEST2                          TABLE

TEST3                          TABLE

DROP时使用purge参数删除的表被直接删除,不存放在回收站。

SQL> drop table test2 purge;

表已删除。

SQL> show recyclebin

ORIGINAL NAME    RECYCLEBIN NAME                OBJECT TYPE  DROP TIME

---------------------------------------------- ------------ -------------------

TEST1            BIN$kUfBJ3qcTSiLxqU6hmoEcw==$0TABLE        2013-02-10:12:17:11

清空回收站

SQL> purge  recyclebin;

回收站已清空。 

SQL> drop table test2;

表已删除。

SQL> show recyclebin

ORIGINAL NAME    RECYCLEBIN NAME                OBJECT TYPE  DROP TIME

---------------------------------------------- ------------ -------------------

TEST2            BIN$UabVC8wiRx+GdsN4VT5bRw==$0TABLE        2013-02-12:17:10:46

SQL> drop table test3;

表已删除。

SQL> show recyclebin

ORIGINAL NAME    RECYCLEBIN NAME                OBJECT TYPE  DROP TIME

---------------------------------------------- ------------ -------------------

TEST2            BIN$UabVC8wiRx+GdsN4VT5bRw==$0TABLE        2013-02-12:17:10:46

TEST3            BIN$n8CZgrwoSRO16TFB/dXOcA==$0TABLE        2013-02-12:17:11:35

清除回收站中的test2表。

SQL> purge tabletest2;

表已清除。

SQL> show recyclebin

ORIGINAL NAME    RECYCLEBIN NAME                OBJECT TYPE  DROP TIME

---------------------------------------------- ------------ -------------------

TEST3            BIN$n8CZgrwoSRO16TFB/dXOcA==$0TABLE        2013-02-12:17:11:35

SQL> flashback table test3 to before drop;

闪回完成。

SQL> show recyclebin

SQL> select count(*) from test3;

 COUNT(*)

----------

        2