Oracle Archive Mode - SQL

Introduction

Oracle Archive Mode is a feature that allows for the automatic archiving of redo log files. Redo log files are used by Oracle databases to record changes made to the database. Enabling archive mode ensures that all changes made to the database are safely stored in archived redo log files. This enables point-in-time recovery, replication, and data mining operations.

In this guide, we will discuss how to enable archive mode in Oracle using SQL statements.

Prerequisites

• Oracle database installed and accessible.
• Privileges to execute SQL statements.

Enabling Archive Mode

To enable archive mode in Oracle, follow these steps:

1. Connect to the Oracle database using SQL*Plus or any SQL client.

2. Check the current log mode of the database by executing the following SQL statement:

   SELECT LOG_MODE FROM V$DATABASE;
   

   Make sure the log mode is NOARCHIVELOG. If it is already in ARCHIVELOG mode, then archive mode is already enabled.

3. Shutdown the Oracle database if it is running:

   SHUTDOWN IMMEDIATE;
   

4. Mount the database:

   STARTUP MOUNT;
   

5. Enable archive mode:

   ALTER DATABASE ARCHIVELOG;
   

6. Open the database:

   ALTER DATABASE OPEN;
   

7. Verify that archive mode is enabled:

   SELECT LOG_MODE FROM V$DATABASE;
   

   The log mode should now be ARCHIVELOG.

Conclusion

Enabling archive mode in Oracle using SQL statements provides a mechanism for the automatic archiving of redo log files. This allows for point-in-time recovery, replication, and other operations requiring access to historical changes made to the database. By following the steps outlined in this guide, you can enable archive mode in your Oracle database and ensure the safety and integrity of your data.