CONTROLFILE_TYPE
After solving ORA-01610, you might have a question: how do I know the currently used controlfile is a BACKUP one or not?
We take the following steps to check the type of controlfile.
Startup DB to Mount
We should mount the database, in order to access the controlfile.
For idle to mount.
SQL> startup mount;
For nomount to mount.
SQL> alter database mount;
Database altered.
There're more variations to start an Oracle database.
Query Controlfile
To know what the type of controlfile is, we query the dynamic view V$DATABASE like this:
BACKUP
SQL> select controlfile_type from v$database;
CONTROL
-------
BACKUP
As you can see, the current controlfile is a BACKUP one.
STANDBY
If it's a standby database, you'll see the result like the following.
SQL> select controlfile_type from v$database;
CONTROL
-------
STANDBY
It's a STANDBY controlfile currently.
Open to READ WRITE
Once the BACKUP or STANDBY database was opened or activated to READ WRITE, the type of controlfile was back to CURRENT. That completes the life cycle of a controlfile.
SQL> select controlfile_type from v$database;
CONTROL
-------
CURRENT
So far, we have introduced 3 types of controlfile, which are CURRENT, BACKUP and STANDBY.