How can you use backup and recovery to manage data changes?

1 Types of backup

There are two main types of backup: physical and logical. Physical backup copies the files that store the data, such as data files, control files, and redo logs. Logical backup extracts the data and its structure, such as tables, indexes, and views, using tools like Data Pump or SQL*Plus. Depending on your needs, you can choose a full backup, which includes all the data, or an incremental backup, which only includes the changes since the last backup.

2 Types of recovery

There are also two main types of recovery: complete and incomplete. Complete recovery restores the database to the most recent state, using the backup files and the redo logs. Incomplete recovery restores the database to a previous point in time, using the backup files and a subset of the redo logs. You can use incomplete recovery when you need to undo unwanted changes, such as accidental deletion or corruption.

3 Recovery Manager

Recovery Manager (RMAN) is a tool that simplifies the backup and recovery process for Oracle databases. RMAN can automate the backup and recovery tasks, such as scheduling, compression, encryption, and validation. RMAN can also perform backup and recovery operations across different platforms, such as Windows, Linux, or cloud. RMAN can integrate with other tools, such as Oracle Enterprise Manager or Data Guard, to enhance the backup and recovery capabilities.

4 Flashback technology

Flashback technology is a feature that allows you to quickly and easily restore the database or its objects to a previous state, without using backup files or redo logs. Flashback technology uses undo data, which is stored in the undo tablespace, to reconstruct the past versions of the data. You can use flashback technology to perform tasks such as recovering dropped tables, undoing transactions, or comparing data changes.

5 Patching and upgrading

Patching and upgrading are common activities that involve changing the database software or structure. Before applying any patch or upgrade, you should always perform a backup of the database and its configuration files, such as init.ora or spfile.ora. This way, you can restore the database to its original state in case of any errors or compatibility issues. You should also test the patch or upgrade on a separate environment, such as a sandbox or a clone, before applying it to the production database.

6 Best practices

To use backup and recovery effectively to manage data changes, you should plan your strategy according to business requirements, such as availability, performance, and security. It's important to document procedures and policies, and keep them updated and accessible. You should also monitor and verify operations regularly, resolving any errors or warnings promptly. Additionally, review and test scenarios periodically to ensure you have the necessary resources and skills to perform them.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?