The control files of a database store the status of the physical structure of the database.
Controlfile Contains the following type of information:
- Archive log history
- Tablespace and datafile records (filenames, datafile checkpoints, read/write status, offline or not)
- Current redo log file sequence number
- Database’s creation date
- database name
- current archive log mode
- Backup information
- Database block corruption information
- Database ID, which is unique to each DB Multiplexing Control file using SPFILE:
SQL>ALTER SYSTEM SET control_files=
C:\oracle\product\10.2.0\oradata\dba01\CONTROL01.CTL’, ‘C:\oracle\product\10.2.0\oradata\dba01\CONTROL02.CTL’, ‘C:\oracle\product\10.2.0\oradata\dba01\CONTROL03.CTL’, ‘C:\oracle\product\10.2.0\oradata\dba01\CONTROL04.CTL’ SCOPE=spfile;
SQL> shutdown;
C:>copy C:\oracle\product\10.2.0\oradata\dba01\CONTROL01.CTL C:\oracle\product\10.2.0\oradata\dba01\CONTROL04.CTL
startup;
Multiplexing Control file using SPFILE:
- shutdown
- C:>copy C:\oracle\product\10.2.0\oradata\dba01\CONTROL01.CTL C:\oracle\product\10.2.0\oradata\dba01\CONTROL04.CTL
- Add new file in the PFILE
control_files=’C:\oracle\product\10.2.0\oradata\dba01\control01.ctl’,’C:\oracle\product\10.2.0\oradata\dba01\control02.ctl’,’C:\oracle\product\10.2.0\oradata\dba01\control03.ctl’,’C:\oracle\product\10.2.0\oradata\dba01\control04.ctl’
- startup pfile=íC:\oracle\product\10.2.0\admin\dba01\pfile\init.ora’;