Oracle Database Replication

1. Replication of Oracle Database Made Easy

2. Oracle is a very popular on-premises relational database system that can be used for a wide range of workloads. These include data warehouse loads, transactions, and mixed loads. A recent version of Oracle is a completely managed service. Oracle is ideal as an analysis tool and managing ETL pipelines as well as a comprehensive querying layer. Critical applications can be easily run-on Oracle because of its stability and short recovery times.

4. Very common use in the ETL ecosystem is the need for Oracle database replicationto another database. This process is primarily done to combine data from Oracle with the data from other sources to get to deeper analysis results.  • Oracle has exclusive tools for Oracle database replicationand integrates with other databases. Here are some of the methods used for replication. • In the first method, the full dump of the table that has to be replicated is taken in specific time intervals to generate a snapshot of the required format. This dump file can be used to load another table into a different data warehouse or execute some other custom transformations. One issue with this method is that it is generally effective with smaller tables but then, it is very reliable for tables in an ETL.  • Here, a trigger is configured to execute when pre-determined events occur. Triggers can be configured so that when a table is modified in Oracle database replication, a record is inserted into another table which can be used to replicate the Oracle data by some custom code to a target database. This trigger-based method is synchronous process because unless the triggers are completely executed, the transactions in the source database will not be successful. However, this problem can be avoided by using a multi-master replicated instance of Oracle as the source database. 

5. This method uses Oracle Golden Gate Change Data Capture (CDC) which is the solution provided by Oracle for all things that are related to ETL with Oracle database as the source for replication. Golden Gate is a paid offering from Oracle that can link up to several target databases through in-built handlers. The Golden Gate’s Kafka handler helps businesses to set up customized pipelines in case the target database handler is not available in Golden Gate.  • Golden Gate works on binary log-based Oracle database replication.These binary logs are historical data of all changes made in an Oracle database since its creation. The biggest benefit of Golden Gate is that it provides real-time support to a large number of target databases through its handlers. It also facilitates transformation of data while loading to a target database.  • Here too there are a few drawbacks. It is a complex process and requires an expert to get the Oracle database replication right. Golden Gate also has a slow first-time load.  • As seen from the above, the selected method for Oracle database replication depends on specific needs of organizations.