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Three Types of Data guard Protection Modes Maximum Availability This mode provides the highest level of data protection that is possible without compromising the availability of a primary database.The transactions do not commit until all redo data needed to recover those transactions has been written to the online redo log …

Logical Standby Databases A logical standby database is initially created as an identical copy of the primary database, but it later can be altered to have a different structure. The logical standby database is updated by executing SQL statements. This allows users to access the standby database for queries and …

Standby Database Types A standby database is a transactionally consistent copy of an Oracle production database that is initially created from a backup copy of the primary database. Once the standby database is created and configured, Data Guard automatically maintains the standby database by transmitting primary database redo data to …

Introduction to Oracle DataGuard Oracle Data Guard ensures high availability, data protection, and disaster recovery for enterprise data. Data Guard provides a comprehensive set of services that create, maintain, manage, and monitor one or more standby databases to enable production Oracle databases to survive disasters and data corruptions. Data Guard …

RMAN Virtual Private Catalogs About Virtual Private Catalogs By default, all of the users of an RMAN recovery catalog have full privileges to insert, update, and delete any metadata in the catalog. For example, if the administrators of two unrelated databases share the same recovery catalog, each administrator could, whether …

RMAN Backup Optimization If you enable backup optimization, then the BACKUP command skips backing up files when the identical file has already been backed up to the specified device type. If RMAN determines that a file is identical and it has already been backed up, then it is a candidate …

RMAN Backup Retention Policy The backup retention policy specifies which backups must be retained to meet your data recovery requirements. This policy can be based on a recovery window or redundancy. Use the CONFIGURE RETENTION POLICY command to specify the retention policy. Configuring a Redundancy-Based Retention Policy The REDUNDANCY parameter of …

RMAN Channels The RMAN client directs database server sessions to perform all backup and recovery tasks. What constitutes a session depends on the operating system. For example, on Linux, a server session corresponds to a server process, whereas on Windows it corresponds to a thread within the database service. The …

Recovery Manager Architecture The Recovery Manager environment consists of the various applications and databases that play a role in a backup and recovery strategy. Component Description RMAN client The client application that manages backup and recovery operations for a target database. The RMAN client can use Oracle Net to connect …

Verifying Security Access with Auditing What Is Auditing? Auditing is the monitoring and recording of selected user database actions, from both database users and non database users. You can base auditing on individual actions, such as the type of SQL statement executed, or on combinations of data that can include …