#oracle database replication

A very popular on-premises relational database system is Oracle. The database can be optimized for use with a variety of workloads such as data warehouse loads, mixed loads, and transactions. One of the main advantages of the Oracle database is that it is ideal as an analysis tool and for managing ETL pipelines as a comprehensive querying layer. Critical applications can be easily operated on Oracle because of its inherent stability and short recovery times.

A very common factor in the ETL ecosystem is the need for Oracle database replication to another database. It is done to combine data from Oracle with other sources to maximize data analytics.

Before going into the many aspects of Oracle database replication, it is necessary to understand what is database replication. In a nutshell, it is the process where data from one source is replicated and stored in different locations, thereby increasing data accessibility across the network. Database replication is flexible and is very effective in both servers and standalone computers. This data can be stored in a range of options, from cloud-based hosts to on or off-site, and even within the same system. Almost all database technologies such as Microsoft SQL Server or Oracle database have in-built features for replication. In other instances, specialized database replication software is used.

The most technologically advanced tools and methods are used for Oracle database replication.

·        In the first method, a snapshot of the needed format is generated by taking the full dump of the table to be replicated at fixed periods. The dump file generated is then used to load another table into a different data warehouse or to execute any other customized transformation. However, the shortcoming of this method is that it is effective in the case of small tables but then, it can be also used for tables in an ETL.

·        In the second method, when pre-set events occur, configured triggers are executed. One of the trigger configurations is when a table is modified in Oracle database replication. At this time, a record is inserted into another table which is then used to replicate the Oracle data to a target database through a custom code. This trigger-based method is synchronous process because unless the triggers are completely carried through, the transactions in the database will not be successful.

·        Finally, there is the Oracle Golden Gate Change Data Capture (CDC). It is the solution for all things that are related to ETL for Oracle database replication. Golden Gate is based on binary logs that are historical data of all changes made in an Oracle database since its creation. The key benefit of this method is real-time support to a large number of target databases. The handlers facilitate the data transformation when a target database is loaded.

One of the most popular on-premises relational database systems is Oracle. It can be used for a variety of workloads such as data warehouse loads, mixed loads, and transactions. The advantage of Oracle is that it is ideal as an analysis tool and for managing ETL pipelines as a comprehensive querying layer. Because of its inherent stability and short recovery times, critical applications can be easily run on Oracle.

A very common factor in the ETL ecosystem is the need for Oracle database replication to another database. It is done to combine data from Oracle with that from other sources to maximize data analytics and results.

What is database replication?  

It is the process where data from one source is replicated and stored in different locations, thereby increasing data accessibility across the network. Database replication is very effective in both servers and standalone computers and this data can be stored in cloud-based hosts, on or off-site, or within the same system. Almost all database technologies such as Microsoft SQL Server or Oracle database have in-built features for replication. In other instances, specialized database replication software is used.

For Oracle database replication, special tools and methods are used. The most widely used ones are:.

·        In the first method, the full dump of the table to be replicated is taken at fixed periods to generate a snapshot of the needed format. The dump file generated is then used to load another table into a different data warehouse or to execute any other customized transformation. One downside of this method is that it is effective in the case of small tables but then, it can be also used for tables in an ETL.

·        In another method, triggers are configured to be executed when pre-set events occur. One of the trigger configurations is when a table is modified in Oracle database replication. At this time, a record is inserted into another table which is then used to replicate the Oracle data to a target database through a custom code. This method based on a trigger is a synchronous process because unless the triggers are completely carried through, the transactions in the database will not be successful. This problem though can be skirted by using a multi-master replicated instance of Oracle as the source database.

·        Finally, there is the Oracle Golden Gate Change Data Capture (CDC). It is the solution for all things that are related to ETL for Oracle database replication. Golden Gate is based on binary logs that are historical data of all changes made in an Oracle database since its creation. The main benefit here is that it provides real-time support to a large number of target databases through its handlers and facilitates the transformation of data while loading a target database.