Oracle introduced in database 10g new feature called "Recycle Bin" to store the dropped database objects.
If any table is dropped then any associated object to this table such as indexes, constraints and any other dependent object are renamed with a prefix of bin$$.
Use of Recycle BinIf user drop an important object accidentally, and he want to get it again.
With Recycle Bin feature user can easily restore the dropped objects.
Enable and Disable Recycle BinYou can use the below query to distinguish which Recycle Bin is enabled or no
SELECT Value FROM V$parameter WHERE Name = 'recyclebin';
It will return on or off
on means that Recycle Bin is enabled and off is disabled.
You can enable and disable Recycle Bin per session and system, there fore you can use the below scripts to enable and disable Recycle Bin per session or system.
ALTER SYSTEM SET recyclebin = ON; ALTER SESSION SET recyclebin = ON; ALTER SYSTEM SET recyclebin = OFF; ALTER SESSION SET recyclebin = OFF;