User-managed backup refers to the use of OS commands to back up physical database files.
Back up database
Database Consistency backup: After the database is closed, the physical files of the database are backed up. At this time, the scn values of the data files are exactly the same. Therefore, it is called Database Consistency backup or cold backup, which is suitable for archive mode and non-archive mode.
Temporary understanding of user-managed cold backup: Use the OS command to directly copy physical database files in the database shutdown state.
Database non-consistent backup: backs up the physical files of the database in the open state, and the database content may change, resulting in inconsistent data file scn. Therefore, it is called the database's non-consistent backup or hot backup, only applicable to archive mode.
Full recovery based on user management (in archive Mode)
1. Back up physical database files in the open state (Database non-consistent backup, hot backup, without affecting business operations)
2. delete data files to simulate file loss (only all data files are deleted; control files and other files are in normal state)
3. Restore data files
4. Application archiving logs
5. Check whether the data is completely restored.
SQL> conn evan/evan
Connected.
SQL> insert into t_evan values ('oracle ');
1 row created.
SQL> insert into t_evan values ('java ');
1 row created.
SQL> commit;
Commit complete.
SQL> select * from t_evan;
TEXT
--------------------------------------------------------------------------------
Oracle
Java
-- Sysdba backup
SQL> conn/as sysdba
Connected.
SQL> select name from v $ datafile;
NAME
--------------------------------------------------------------------------------
/Oracle/10g/oracle/product/10.2.0/oradata/oralife/system01.dbf
/Oracle/10g/oracle/product/10.2.0/oradata/oralife/undotbs01.dbf
/Oracle/10g/oracle/product/10.2.0/oradata/oralife/sysaux01.dbf
/Oracle/10g/oracle/product/10.2.0/oradata/oralife/users01.dbf
/Oracle/10g/oracle/product/10.2.0/oradata/oralife/example01.dbf
SQL> alter database begin backup;
Database altered.
SQL> host cp/oracle/10g/oracle/product/10.2.0/oradata/oralife/*. dbf/oracle/10g/oracle/bakup/database/-- back up all data files
SQL> alter database backup controlfile to '/oracle/10g/oracle/bakup/database/oralife. ctl'; -- backup control file
Database altered.
Certificate -----------------------------------------------------------------------------------------------------------------------------------------
Forget alter database end backup;
Certificate -----------------------------------------------------------------------------------------------------------------------------------------
SQL> alter system archive log current; -- archive the current log Group
System altered.
Use rm to delete all data files (*. dbf );
SQL> conn evan/evan
Connected.
SQL> select * from t_evan;
TEXT
--------------------------------------------------------------------------------
Oracle
Java
SQL> insert into t_evan values ('spring ');
1 row created.
SQL> commit;
Commit complete.
SQL> ALTER SYSTEM CHECKPOINT; -- refreshes modified data from the cache to the disk, and updates control files and data files.
System altered.
SQL> ALTER SYSTEM SWITCH LOGFILE; -- log SWITCH
System altered.
View the alter_oralife.log error message: the file does not exist and so on...
Complete recovery
Copy the backup data file to the specified destination location for recovery
SQL> recover database -- open status
ORA-00283: recovery session canceled due to errors
ORA-01124: cannot recover data file 1-file is in use or recovery
ORA-01110: data file 1:
'/Oracle/10g/oracle/product/10.2.0/oradata/oralife/system01.dbf'
SQL> shutdown immediate -- open status
ORA-01122: database file 1 failed verification check
ORA-01110: data file 1: '/oracle/10g/oracle/product/10.2.0/oradata/oralife/system01.dbf'
ORA-01208: data file is an old version-not accessing current version
SQL> startup force mount; -- enters the mount State to restore
ORACLE instance started.
Total System Global Area 528482304 bytes
Fixed Size 1220360 bytes
Variable Size 163578104 bytes
Database Buffers 356515840 bytes
Redo Buffers 7168000 bytes
Database mounted.
SQL> recover database
Media recovery complete.
SQL> alter database open;
Database altered.
SQL> conn evan/evan -- use evan to log on to view the recovery status
Connected.
SQL> select * from t_evan;
TEXT
--------------------------------------------------------------------------------
Oracle
Java
Spring
There are no application archiving logs. There are several ways to archive application logs.
Specify log: {<RET> = suggested | filename | AUTO | CANCEL}
When restoring a data file in the open state, you should offline it and restore it online. All the recovery should be completed in the open state as much as possible.
To understand checkpoint, alter system archive log current;, ALTER SYSTEM SWITCH LOGFILE
