What is Control file ?

[Former Member]

Hi Gurus,

Please explain me that what is Control file and what was the purpose of it in SAP Oracle DataBase.

Thanks.

[Former Member]

ThanQ guys for your help

[Former Member]

Thank You Sumit and Fidel to solve my doubts.

[Former Member]

Hi Kalyan

If your doubt is solved please mark this as answered.

The correct way to thank is to give relevant points to the user.

Regards

Sumit

Message was edited by:

Sumit Jain

[Former Member]

Hi Kalyan

<b>What Is a Control File?</b>

Every Oracle Database has a control file, which is a small binary file that records the physical structure of the database. The control file includes:

The database name

Names and locations of associated datafiles and redo log files

The timestamp of the database creation

The current log sequence number

Checkpoint information

The control file must be available for writing by the Oracle Database server whenever the database is open. Without the control file, the database cannot be mounted and recovery is difficult.

The control file of an Oracle Database is created at the same time as the database. By default, at least one copy of the control file is created during database creation. On some operating systems the default is to create multiple copies. You should create two or more copies of the control file during database creation. You can also create control files later, if you lose control files or want to change particular settings in the control files.

<b>Guidelines for Control Files</b>

This describes guidelines you can use to manage the control files for a database, and contains the following topics:

Provide Filenames for the Control Files

Multiplex Control Files on Different Disks

Back Up Control Files

Manage the Size of Control Files

Role of Control File will remain the same even when you use Oracle with SAP. Just there will be some more entries in the file.

Refer the link below as well:

http://download-east.oracle.com/docs/cd/B19306_01/server.102/b14231/control.htm#i1006143

Hope this should clear you doubt.

Regards

Sumit Jain

[Reward with points if useful]

Message was edited by:

Sumit Jain

[Former Member]

Hello,

I think that the best explanation can be found on the oracle documentation. On the Oracle9i Database Concepts Release 2 (9.2) you can find the following:

<a href="http://download-uk.oracle.com/docs/cd/B10501_01/server.920/a96524/c04space.htm#10136">Control Files Overview</a>

Its purpose is to contain <u>essential information</u> about the ORACLE database. Without this file Oracle database will not be able to start.

Regards