Oracle GoldenGate

Oracle GoldenGate is Oracle’s strategic logical replication solution for data distribution and data integration.

Oracle GoldenGate offers a real-time, log-based change data capture and replication software platform. The software provides capture, routing, transformation, and delivery of transactional data across heterogeneous databases in real time.

Unlike replication solutions from other vendors, Oracle GoldenGate is more closely integrated with Oracle AI Database while also providing an open, modular architecture ideal for replication across heterogeneous database management systems. This combination of attributes eliminates compromise, making Oracle GoldenGate the preferred logical replication solution for addressing requirements that span Oracle AI Database and non-Oracle AI Database environments.

A typical environment includes a capture, pump, and delivery process. Each of these processes can run on most of the popular operating systems and databases, including Oracle AI Database. All or a portion of the data can be replicated, and the data within any of these processes can be manipulated for not only heterogeneous environments but also different database schemas, table names, or table structures. Oracle GoldenGate also supports bidirectional replication with preconfigured conflict detection and resolution handlers to aid in resolving data conflicts.

Oracle GoldenGate logical replication enables all databases in an Oracle GoldenGate configuration, both source and target databases, to be open read-write. This makes it a key component of MAA for addressing a broad range of high availability challenges for zero downtime maintenance, cross platform migration, and continuous data availability, specifically:

Zero or near zero downtime maintenance. In this architecture, Oracle GoldenGate provides greater flexibility than the capabilities provided by Data Guard. Oracle GoldenGate source and target databases can have a different physical and logical structure, can reside on different hardware and operating system architectures, can span wide differences in Oracle AI Database releases (for example, 19c to 26ai), or be a mix of Oracle and non-Oracle systems. This allows for the modernization of 24x7 servers and allows new Oracle features to be implemented without impacting the availability of the databases. Maintenance is first performed on a target database while production runs on the source. After the maintenance is complete, production can be moved to the source all at once, similar to a Data Guard switchover. Optionally, bidirectional replication can be used to gradually move users over to the new system to create the perception of zero downtime. In either case, Oracle GoldenGate replication can be enabled in the reverse direction to keep the original source database synchronized during a transition period, making it simple to effect a planned fall-back to the previous version if needed, with minimal downtime and no data loss.
Zero or near-zero downtime migrations when a Data Guard solution is not applicable. Platform or database migrations can be carried out using Oracle GoldenGate as the data synchronization method between the old and new systems. Once the database has been instantiated on another host, Oracle GoldenGate is configured to replicate changes from the production database. A guaranteed restore point can be created on the migrated database so that after user testing the database can be flashed back, and Oracle GoldenGate can apply any outstanding data changes from the production database before moving the application users to the new database, similar to a snapshot standby database. If desired, bi-directional replication can also be configured from the migrated database back to the production database for use as a fallback solution.
Zero or near-zero downtime application upgrades. Application upgrades that modify back-end database objects typically result in significant planned downtime while maintenance is being performed. Oracle GoldenGate replication enables data transformations that map database objects used by a previous version of an application to objects modified by the new version of an application. This enables database maintenance to be performed on a separate copy of the production database without impacting the availability of the application. After the maintenance is complete and Oracle GoldenGate has finished synchronizing old and new versions, users can be switched to the new version of the application.
Read-write access to a replica database while it is being synchronized with its source database. This is most often used to offload reporting to a copy of a production database when the reporting application requires a read-write connection to database in order to function. This is also relevant to disaster recovery environments where the nature of the technology used for the application tier requires an active read-write connection to the DR database at all times in order to meet recovery time objectives.
Active-Active replication. Oracle GoldenGate supports an active-active multi-directional configuration, where there are two or more systems with identical sets of data that can be changed by application users on either system. Oracle GoldenGate replicates transactional data changes from each database to the others to keep all sets of data current.
Seamless moves between Oracle Real Application Clusters (RAC) nodes in the event of database instance failure or during applicable maintenance operations. This ability provides high availability with Oracle GoldenGate and it is possible to patch and upgrade the Oracle GoldenGate software on one or more nodes in the cluster without affecting the node where Oracle GoldenGate is currently running. Then at a predetermined time, Oracle GoldenGate can be switched to one of the upgraded nodes. The switch is done without reconfiguring Oracle GoldenGate because configuration information is shared across the Oracle RAC cluster.

See Also:

Oracle GoldenGate Documentation

http://www.oracle.com/goto/maa for Oracle MAA Oracle GoldenGate technical briefs