Simulate and repair data block corruption in Oracle

In Oracle databases, we may experience a lot of data corruption and how it is important to recover data in the face of these situations. In many cases, recovery is extremely complex and requires careful, reckless operations and attempts that can result in permanent corruption of the database.
So I recommend that you make a data backup before you try to recover.

For important databases, it is advisable to consult a professional to avoid unnecessary data loss if the recovery steps and operational consequences are not determined.

This paper attempts to simulate and solve the problem of data block damage, and it is a kind of database damage recovery discussion

1. Inserting data

E:\oracle\ora92\bin>sqlplus "/As SYSDBA"
Sql*plus:release 9.2.0.4.0-production on Monday March 8 20:27:15 2004
Copyright (c) 1982, 2002, Oracle Corporation. All rights reserved.
Connect to:
Oracle9i Enterprise Edition Release 9.2.0.4.0-production
With the partitioning, OLAP and Oracle Data Mining options
Jserver Release 9.2.0.4.0-production
Sql> select name from V$datafile;
NAME
--------------------------------------------------------------------------------
E:\ORACLE\ORADATA\EYGLE\SYSTEM01. Dbf
E:\ORACLE\ORADATA\EYGLE\UNDOTBS01. Dbf
E:\ORACLE\ORADATA\EYGLE\EYGLE01. Dbf
Sql> Create tablespace block
2 datafile ' e:\oracle\oradata\eygle\block.dbf '
3 Size 1M
4 extent management Local;
The table space has been created.
sql> alter user eygle default tablespace block;
The user has changed.
sql> ALTER user Eygle Quota unlimited on block;
The user has changed.
Sql> Connect Eygle/eygle
is connected.
Sql> CREATE TABLE T as select * from Dba_users;
Table has been created.
sql> INSERT INTO T-select * from T;
8 lines have been created.
Sql>/
16 lines have been created.
Sql>/
32 lines have been created.
Sql>/
64 lines have been created.
Sql>/
128 lines have been created.
Sql>/
256 lines have been created.
Sql>/
512 lines have been created.
Sql>/
1024 lines have been created.
Sql>/
2048 lines have been created.
Sql>/
4096 lines have been created.
Sql>/
INSERT INTO t select * from t
*
ERROR is on line 1th:
ORA-01653: Table eygle.t cannot be extended through 8 (in table space block)
Sql> commit;
Submit completed.
Sql> alter system checkpoint;
The system has changed.
Sql> Select COUNT (*) from T;
COUNT (*)
----------
8192
Sql> Connect/as SYSDBA
is connected.
sql> shutdown Immediate
The database has been closed.
The database has been unloaded.
The ORACLE routine has been closed.