Capture From Oracle Data Guard

Fivetran HVR can perform log-based capture from a Data Guard (DG) physical standby database (also called as non-active DG), as well as from Active Data Guard (ADG) physical standby database using direct capture.

HVR does not support capture from a DG physical standby database when capturing from Oracle using LogMiner.

Prerequisites

To capture changes from a DG or ADG physical standby database, the following must be performed:

• Configure the standby database as the HVR location (see below) and define action Capture for the location.
• Configure archiving on the standby database.
• Set the necessary log-based capture grants.
• Configure supplemental logging on the primary database.

Data Guard

To capture changes from DG, the HVR source location must be configured with two connections, one to the physical standby database for access to the redo and one to the primary database to access data (for example, to run Refreshing Data).

• HVR needs a connection to the standby database to query the system views about the current state of redo files. With a DG physical standby database that is in a mounted state as the source, this user must have a sysdba privilege.
• HVR needs a connection to the primary database to do all standard operations like Activate Replication, Refreshing Data and Comparing Data. It is assumed that the primary database is reachable from the host of the standby database through a regular TNS connection.

Connection Parameters for Data Guard

In HVR UI, while creating an Oracle location with Data Guard, in Step 3. Configure Location Connection, the connection parameters for the standby database must be supplied. And, in Step 4. Configure Capture/Integrate, the connection parameters for the primary database must be supplied.

Grants for Capturing from Data Guard

The HVR database User must have a sysdba privilege to capture changes from a DG physical standby database.

Active Data Guard

HVR can also capture from an Oracle database that was previously a Data Guard physical database target. If HVR was capturing changes from one primary Oracle database and a lossless role transition occurs (so that a different Data Guard physical standby database becomes the new primary one), HVR can continue capturing from the new primary, including capturing any changes which occurred before the transition. This process is automatic providing that the HVR location is connecting to Oracle in a way which 'follows the primary'. When the capture job connects to the database again, it will continue to capture from its last position (which is saved on the hub machine).

In HVR UI, while creating an Oracle location with Active Data Guard, you need to supply only the connection parameters for the standby database in Step 3. Configure Location Connection.

Operator intervention is required if a failover took place requiring an OPEN RESETLOGS operation to open the primary database. To start reading transaction logs after OPEN RESETLOGS, perform Activate Replication with option Table Enrollment.

Grants for Capturing from Active Data Guard

• The HVR database User must have the privileges described in Grants for Log-Based Capture to capture changes from an ADG physical standby database.