After connect to the database via SQLPLUS. Shutdown the database using the NORMAL, IMMEDIATE, or TRANSACTIONAL option.
SQL> select * from v$version;
BANNER CON_ID
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Oracle Database 12c Standard Edition Release 12.2.0.1.0 - 64bit Production 0
PL/SQL Release 12.2.0.1.0 - Production 0
CORE 12.2.0.1.0 Production 0
TNS for Linux: Version 12.2.0.1.0 - Production 0
NLSRTL Version 12.2.0.1.0 - Production 0
SQL> archive log list
Database log mode No Archive Mode
Automatic archival Disabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 129
Current log sequence 131
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
We can start the database with mount mode.
SQL> startup mount
ORACLE instance started.
Total System Global Area 6375342080 bytes
Fixed Size 8634896 bytes
Variable Size 1375735280 bytes
Database Buffers 4982833152 bytes
Redo Buffers 8138752 bytes
Database mounted.
Now, we can alter the database to archive log mode, then open the database. As it can be seen from the following command, current log mode is archive mode.
SQL> alter database archivelog;
Database altered.
SQL> alter database open;
Database altered.
SQL> archive log list
Database log mode Archive Mode
Automatic archival Enabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 129
Next log sequence to archive 131
Current log sequence 131
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