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This article mainly introduces "how Oracle performs data backup". In daily operation, I believe many people have doubts about how Oracle performs data backup. Xiaobian consulted all kinds of information and sorted out simple and easy operation methods. I hope to help you answer the doubts of "how Oracle performs data backup"! Next, please follow the small series to learn together!

Use the following methods to perform backups:

Recovery Manager

Oracle Secure Backup

user-managed backup

Recovery Manager (RMAN) is the recommended method for Oracle DB backups.

Oracle Secure Backup complements existing functionality by adding backup to tape and network backup capabilities.

User-managed backups are script-based, so DBAs must write scripts. This method is gradually being phased out because

It requires more labor.

Oracle Secure Backup

Oracle Secure Backup and RMAN together are Oracle environments

Provides an end-to-end backup solution:

- Centralized tape backup management for file system data and Oracle DB

- Use the best integrated media management layer for RMAN backups

- Backup any data anywhere on the network

Provides a single technical support resource for a holistic backup solution that accelerates decision making

speed of the problem.

Ensure reliable data protection at low cost and complexity.

Oracle Secure Backup

Oracle's current product for database backup and recovery is Recovery Manager. Oracle Secure Backup

Complements existing functionality in the following ways:

Complete backup solution: Oracle Secure Backup provides data protection for database and non-database data

This protects the entire Oracle environment.

Media Management: Oracle Secure Backup provides media management for database backups from RMAN backups to tape

Layer. Prior to Oracle Secure Backup, customers needed to purchase expensive tapes with RMAN integration

Third-party media management products for backup capabilities.

Backup anywhere on the network: Oracle Secure Backup backs up computers connected to the network from multiple computers

All data from the computer system to tertiary storage resources on the network. Oracle Secure Backup Support for Services

Different configurations of servers, clients, network-attached storage (NAS) servers, and tertiary storage devices, and protect network storage

Storage environment.

The combination of RMAN and Oracle Secure Backup provides an end-to-end backup solution for the entire Oracle product family.

Because Oracle Corporation is responsible for the overall backup solution, the solution provides better customer support

Services.

Oracle Secure Backup

Oracle's current product for database backup and recovery is Recovery Manager. Oracle Secure Backup

Complements existing functionality in the following ways:

Complete backup solution: Oracle Secure Backup provides data protection for database and non-database data

This protects the entire Oracle environment.

Media Management: Oracle Secure Backup provides media management for database backups from RMAN backups to tape

Layer. Prior to Oracle Secure Backup, customers needed to purchase expensive tapes with RMAN integration

Third-party media management products for backup capabilities.

Backup anywhere on the network: Oracle Secure Backup backs up computers connected to the network from multiple computers

All data from the computer system to tertiary storage resources on the network. Oracle Secure Backup Support for Services

Different configurations of servers, clients, network-attached storage (NAS) servers, and tertiary storage devices, and protect network storage

Storage environment.

The combination of RMAN and Oracle Secure Backup provides an end-to-end backup solution for the entire Oracle product family.

Because Oracle Corporation is responsible for the overall backup solution, the solution provides better customer support

Services.

1)user-managed backup

User-managed schemes:

The process of manually tracking backup requirements and status

Usually using user-written scripts

Database files need to be placed in the correct schema for backup

Depends on operating system commands to back up files

1.1)user-managed backup

User-managed backups can be performed interactively. However, it is often necessary to write scripts to perform backups. Operational scenarios

There are multiple scenarios that must be scripted to handle.

Here are some of the actions the script must perform:

Query v$datafile to determine which data files need to be backed up and their current state

Query v$logfile to identify online redo log files

Query v$controlfile to identify the control file to back up

Place each table space in online backup mode

Query v$backup to see which data files are contained in tablespaces in online backup mode

Issue an operating system copy command to copy data files to a backup location

Take each table space out of online backup mode

Backup policies may include:

- Whole database (whole)

- Partial database (partial)

The backup type may indicate that it contains the following:

- All blocks in the selected file (full backup)

- Only information that has changed since a previous backup (incremental backup)

- Cumulative (changes since last level 0 backup)

- Differences (changes since last incremental backup)

Backup modes can be of the following types:

- Offline (consistent backup or cold backup)

- Online (inconsistent or hot backup)

Full database backup: includes all data files and at least one control file (remember all control files in the database

They are all the same).

Partial database backup: may include zero or more tablespaces, zero or more data files; may or may not include

include control file

Full backup: Create a copy of each block of data that contains data and is located in the file to be backed up

Incremental backup: Creates a copy of all data blocks that have changed since a previous backup. Oracle DB supports two

Incremental backups of levels (0 and 1). A level 1 incremental backup can be one of two types: cumulative or differential.

Cumulative backups are used to back up all changes that have occurred since the last level 0 backup. Differential backups are used to backup from the last incremental backup

All changes that have occurred since the backup (which can be a level 0 or level 1 backup).

Offline backup (also known as a "cold" or "consistent" backup): A backup performed without the database open

share. It is called a consistent backup because the system change number (SCN) in the header of the data file matches the control number when the backup is performed.

The SCN in the system file matches.

Online backup (also known as "hot" or "inconsistent" backup): A backup performed while the database is open

share. It is called a non-consistent backup because it is not possible to ensure that the data file and the control file are identical when the database is open.

Synchronization. Non-consistent backups need to be restored before they can be used.

Backups can be stored as:

image copies

backup set

Image copy: refers to a copy of data or archive log files (similar to copying files using only operating system commands).

Backup Set: A collection of one or more binary files containing one or more data files, control files,

Server parameter files or archive log files. When using backup sets, empty data blocks are not stored, so backup sets are on disk

or tape. Compressing backup sets further reduces the space requirements for backups.

A copy of the image must be backed up to disk. Backup sets can be sent to disk or directly to tape.

The advantage of storing backups as image copies is that they improve the granularity of restore operations. When working with an image copy, simply copy from a backup

Location retrieval file. When working with backup sets, you must retrieve the entire backup set from the backup location before you can extract the required

Documents.

The advantage of storing backups as backup sets is that they make better use of space. 20% or more of the data in most databases

Block is empty block. The image copy backs up every block, even if the block is empty. Backup sets can be significantly degraded

Low space required for backup. In most systems, the benefits of backup sets outweigh the benefits of image copies

At this point, the study of "how Oracle performs data backup" is over, hoping to solve everyone's doubts. Theory and practice can better match to help everyone learn, go and try it! If you want to continue learning more relevant knowledge, please continue to pay attention to the website, Xiaobian will continue to strive to bring more practical articles for everyone!

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