Overview of Oracle Data Guard

Data Guard

Here I am going to explain the concept of Oracle Data Guard  in  short and easy way to understand and prepare quickly for the Interviews and  this small small content will help you in gaining the knowledge of Data Guard easily.

 

What is a Oracle Data Guard ?

Oracle Data Guard is a central component of an integrated Oracle Database High Availability ( HA ) Solution set that helps organization ensure business continuity by minimizing the various kind Plan and Unplan Downtime.

 

·         Main purpose of Oracle Data Gaurd is High Availability ( HA ).

·   In Data Guard Configuration, a Production Database is set as Primary Database where as Standby Database called as Synchronized copy of the Primary Database.

·     You can create 1 to 30 Standby Databases in Oracle 11g with the help of the backup copy of Primary Database.

·     Below is the basic Architecture of Oracle Data Guard, with the help of this you can understand the basic overview of the Data Guard.

 

Basic Oracle Data Gaurd Architecture

What is the type of Oracle Standby Data Guard?

There are mainly 4 types of Standby Data Guard, namely…..

1.      Physical Standby Database.

2.      Active Standby Database.

3.      Logical Standby Database.

4.      SnapShot Standby Database.

What is Physical Standby Database ?

Physical Standby Database apply changes on Block to Block basis.

Its basically used to maintain the exact copy of Primary Database through Redo Apply.

Its reduced the workload of primary database and help in Performance and protection.

 

What is Active Standby Database ?

Active Standby Database is also apply changes on Block to Block basis.

Its Open in a Read only mode.

 

What is Logical Standby Database ?

It will be in a open ( Read / Write ) State.

It can be updated by executing SQL statements which help user to reporting any time.

 

 What is SnapShot Standby Database ?

ID Created by converting a physical standby Database.

It mainly used for testing purposes.

It Provides exact replica of Primary Database.

 

What is the type of Data Guard Services ?

There are mainly 3 types of Data Guard Services, namely…

1.      Redo Transport Services.

 

2.      Apply Services.

·         Redo Apply Services.

·         SQL Apply Services.

 

3.      Role Management or Role Transitions Services.

·         Switch Over Services.

                  ·         Fail Over Services.