前提：开启回收站
查看回收站状态
SQL> show parameter recyclebin; NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ recyclebin string ON
SQL> desc test; Name Null? Type ----------------------------------------- -------- ---------------------------- TABLE_NAME NOT NULL VARCHAR2(30) SQL> drop table test; Table dropped. SQL> select original_name,operation,droptime from recyclebin; no rows selected SQL> flashback table test to before drop; flashback table test to before drop * ERROR at line 1: ORA-38305: object not in RECYCLE BIN SQL>
SQL> show user USER is "SYS" SQL>
奇怪，为什么回收站是开的，删除时不进回收站呢？系统表空间是不放入回收站的
scott用户就没有问题：
SQL> show user
USER is "SCOTT"
SQL>create table test as select * from emp;
Table created.
SQL> select count(1) from test;
COUNT(1)
----------
270
SQL> drop table test;
Table dropped.
SQL> select original_name,operation,droptime from recyclebin;
ORIGINAL_NAME OPERATION DROPTIME
-------------------------------- --------- -------------------
TEST DROP 2019-09-11:02:13:37
SQL> flashback table test to before drop;
Flashback complete.
SQL> select count(1) from test;
COUNT(1)
----------
270
SQL>
回收站开启的方法：
alter session set recyclebin=off;
alter system set recyclebin=off DEFERRED;