How to change database from Noarchivelog mode to Archivelog mode.

This document describes how to change database log mode from noarchivelog to archivelog.

Step 1: Check the database log mode.

We can check database log mode in below two ways.

SQL> select name,open_mode,log_mode from v$database;

NAME       OPEN_MODE        LOG_MODE
---------          --------------------       ------------
PRIMARY    READ WRITE        NOARCHIVELOG


SQL> archive log list
Database log mode        No Archive Mode
Automatic archival        Disabled
Archive destination        USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence     8
Current log sequence        10


Step 2: Change log mode from Noarchivelog to Archivelog mode.

Shutdown the  database.

SQL> shut immediate
Database closed.
Database dismounted.
ORACLE instance shut down.

Start the database in mount stage

SQL> startup mount

ORACLE instance started.

Total System Global Area 1560281088 bytes

Fixed Size     2924784 bytes

Variable Size 1006636816 bytes

Database Buffers   536870912 bytes

Redo Buffers    13848576 bytes

Database mounted.

Change database to archivelog mode.

SQL> alter database archivelog;

Database altered.

SQL> alter database open;

Database altered.

Check the log mode.

SQL> select name,open_mode,log_mode from v$database;

NAME           OPEN_MODE        LOG_MODE

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

PRIMARY        READ WRITE        ARCHIVELOG

SQL> archive log list

Database log mode        Archive Mode

Automatic archival        Enabled

Archive destination        USE_DB_RECOVERY_FILE_DEST

Oldest online log sequence     8

Next log sequence to archive   10

Current log sequence        10