Your database is in the MOUNT state and you execute the following command to open it:
ALTER DATABASE OPEN;
What two actions are performed as a result of this command? (Choose two.)
A.
All control files are opened.
B.
All redo log files are opened
C.
The password file is opened.
D.
The parameter file is opened.
E.
All online data files are opened.
The last startup step for an Oracle database is the open stage. When Oracle opens the database, it accesses all of the datafiles associated with the database. Once it has accessed the database datafiles, Oracle makes sure that all of the database datafiles are consistent.
Opening the Oracle Database
To open the database, you can just use the startup command as seen in this example
SQL> startup
If the database is mounted, you can open it with the alter database open command as seen in this example:
SQL> alter database open;
You cannot take tablespaces offline while the database is open in READ ONLY mode. However, you can take datafiles offline and online, and you can recover offline datafiles and tablespaces while the database is open in READ ONLY mode.
ALTER DATABASE OPEN RESETLOGS
And this works, the database is opened and the new redo logs are created.
1. The ALTER DATABASE OPEN should be allowed to read the online redo logs.
2. You can take datafiles offline and online, and you can recover offline datafiles and tablespaces while the database is open in READ ONLY mode ==> OPEN database will take online files
OPEN – REDO – ONLINE