A case of database recovery (1)

Recovery | data | database
Oracle9i rollback segment Table space after the loss of processing methods:

Example of restoring a database with suppressed parameters:

The specific steps are as follows:

First the automatic management of the initial Init.ora file is changed to manual management, then the implied parameters are added:
#undo_management =auto
Undo_tablespace=undotbs
_corrupted_rollback_segments= (_syssmu1$,_syssmu2$,_syssmu3$,_syssmu4$,_syssmu5$,_syssmu6$,_syssmu7$,_syssmu8$, _syssmu9$,_syssmu10$)

Sql>startup mount (Database boot to mount state)
sql> ALTER DATABASE DataFile ' D:\ORACLE\ORADATA\ORCL\UNDOTBS01. DBF ' offline drop;
Database altered.

Sql>alter database open;
Database opened.
Sql> Show Parameter Undo

NAME TYPE VALUE
------------------------------------ ----------- ---------
Undo_management string MANUAL
Undo_retention Integer 900
Undo_suppress_errors Boolean FALSE
Undo_tablespace string Undotbs

Sql> drop tablespace undotbs including contents;
Tablespace dropped.

To rebuild the Undotbs table space:
sql> Create undo tablespace undotbs DataFile ' D:\ORACLE\ORADATA\ORCL\UNDOTBS01. DBF '
Size 100M;
Tablespace created.

sql> shutdown immediate (Close database)
Database closed.
Database dismounted.
ORACLE instance shut down.

Edit Init.ora initialization parameter file, remove implied parameter, set
Undo_management=auto
Undo_tablespace=undotbs
Save the Init.ora file, and then execute
Sql> Startup Mount
ORACLE instance mounted.
Total System Global area 114061244 bytes
Fixed Size 282556 bytes
Variable Size 79691776 bytes
Database buffers 33554432 bytes
Redo buffers 532480 bytes
Database mounted.

Sql>alter database DataFile ' D:\ORACLE\ORADATA\ORCL\UNDOTBS01. DBF ' online;
Database altered.

Sql>alter database open;
Database opened.
Sql> Show Parameter Undo

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
Undo_management string AUTO
Undo_retention Integer 900
Undo_suppress_errors Boolean FALSE
Undo_tablespace string Undotbs