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 -------------------------------------------------------------------------------- ---------- 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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