Detailed description of ORACLE Database Backup Technology

1 Introduction

ORACLE Database is a large relational database that can store terabytes of data. Therefore, it is especially important to ensure the security of such data. We started using the ORACLE database in 1991, over the years, we have developed a complete set of ORACLE Database backup systems. Now we will introduce our backup system for your reference.

2. Determine the database running mode based on actual needs.

ORACLE databases run in two ways: Archive ARCHIVELOG. Archive aims to restore all submitted items to the maximum extent when a database fails; the second is to restore the database to the nearest recycling point without archiving (NOARCHIVELOG. Based on the high availability of the database and the amount of workload that users can afford to lose, we archive the databases that we officially run, and archive the databases that are being developed and debugged.

3. How to change the running mode of the database

3.1 set the running mode of the database during database creation

When creating a database, as part of creating a database, it determines the initial archiving method of the database. Generally, it is in NOARCHIVELOG mode. After the database is created, change the database to archive as needed to ARCHIVELOG.

3.2 change the archive mode to archive

Close the database and back up existing data. Changing the running mode of the database is an important change to the database. Therefore, you must back up the database to protect possible problems.

Start Instance, Mount database, but do not open database, to change the archive Mode

Sqldba lmode = y svrmgrl)

Sqldba> connect internal

Sqldba> startup mount

Sqldba> alter database archivelog;

Enable automatic archiving

Add the following parameters to the initialization file init *. ora (usually under dbs in the lower directory of the ORACLE root directory:

Log_archive_start = true

Specify the redo login file name and storage location for the archive

Add the following parameters to the initialization file init *. ora:

Log_archive_format = % S. arc

Log_archive_dest =/arch12/arch (arch12 is the directory where log files are stored)

Close the database, restart the database, and archive the data.

4. Recycling System

4. 1. The database recovery system depends on the database operation mode and the workload that can be borne by the loss. For non-archiving, we use the ORACLE database logical backup Export. The recovery system is: A full backup (x01.dmp) is performed once a month, and a cumulative backup is performed once a week (c *. dmp), Incremental backup once a day (I *. dmp), specifically, Incremental backup from Monday to Friday, and cumulative backup or full backup on Saturday. After each backup is completed, it is automatically uploaded to other machines for storage. These backups are automatically executed and the program text is provided later.

For the archive method, we use ORCALE physical backup: After the database is created, a physical full backup is performed, without shutting down the database at ordinary times, physical backup of online database data files for frequently-changed data files within one week. When the database structure changes, such as adding tablespaces and data files, such as shutdown allowed, close the database normally, and re-create a full backup of the database. Otherwise, back up the control file and back up the data file as usual. Online log files are written on the array without mirroring or backup.

We have explained so much about the ORACLE Database Backup Technology and hope everyone can gain some benefits.