What is oracle data guard

Oracle data guard is the term(you can call it a feature too) used by oracle and this feature is integrated with oracle RDBMS. Data guard create, maintain, manage and monitor one/more extra databases -called standby database, beside production database. The goal is to survive production databases from any disasters, failure or data corruptions.

At first, an exact replica of production database is created, which referred to as standby database later. Data guard then maintains and keep up to date of these standby databases with of production database. If production database becomes unavailable then data guard can switch standby database to production role and thus minimize the downtime without any data loss.

In addition to availability of production database data guard gives other advantages. Like we can do real time query in standby database, do backup operation in it and thus minimize the load of production database.

There is no restriction about the location of the stand by databases. They can be located thousands miles away from the production database or can be within same room, provided they can communicate each-other.

The more features, configurations, advantage about oracle data guard will be discussed gradually.

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