Solution of Inconsistent Control File

Inconsistent error occur when Oracle detects an inconsistency between the multiplex copies of the control file. All copies of the control file must have the same internal sequence number Typical scenarios in which you may receive this inconsistencu error include:

1. You have restored the control file from backup, but you have forgot to copy it to other locations of the control file as listed in the "CONTROL_FILES" parameter in the initialization parameter.

2. You have moved one or more copies of the control file to a different location while the database was up and running.

3. You someone overwrote one of the copies of the control file with an old copy.

4. You are restoring a database backup that was improperly taken with the database up and running.

To get the solution of these problem start your database with single copy of the control file and then shut the database down and then copy of this good copy of control file to the other locations as listed in the control_files parameter.
Following these steps to solve this problem:

Step 1. If database is still up, shutdown abort.

Step 2. If you use pfile then edit the CONTROL_FILES parameter from init.ora and modify it with one copy of control file.

If you use spfile then after startup nomount use show control_files to see existing controlfiles inside spfile and then you can use ALTER SYSTEM SET CONTROL_FILES=file_name; in order to point just one copy of control file.

Step 3. startup restrict

If instead you get ORA-1122, ORA-1110, and ORA-1207, go back to step 2 and try with another control file.

If you have already tried each and every one of the mirrored copies unsuccessfully, you must create a new control file for the database.

If you get ORA-1113 and ORA-1110 pointing to one of the datafiles, it means the copy of the control file you picked is good, but the referenced datafile must be recovered before the database can be opened.Then RECOVER DATBASE, apply the log it prompt and ALTER DATABASE OPEN.

Step 4. Shutdown the database.
SQL>shutdown

Step 5. Copy this control file and locate to the different locations.

Step 6. Edit the init.ora file CONTROL_FILES parameter to include all location of the copy control files again.

Step 7. Startup database.