23c: Database has been previously opened and closed

While the database is OPEN, we can close the database to the MOUNT status, and we can enable or diable the archivelog, but to OPEN the database we need to stop the instance and start it.

SQL> select status from v$instance;

STATUS
------------
OPEN

SQL>
SQL> alter database close;

Database altered.

SQL>
SQL>
SQL> select status from v$instance;

STATUS
------------
MOUNTED

SQL> alter database close;

Database altered.

SQL>
SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-16196: database has been previously opened and closed

We nead to stop the instance and start again.