However, business needs more than the transactional processing. There are many operations relying on the transaction data to provide services and analysis to improve the business processes. For example,
- Service applications for customers to check their bank statement, order status, mobile usage or trading records
- Accounting applications auditing transactions
- Start the extract at the source DB
- Create the new target DB and import data from source DB to the target DB.
This normally involved the import/export tools or the backup tools like Oracle RMAN.
- Start the replicat at the new DB with HANDLECOLLISIOINS.
The collisions only happens if there are transactions after extract is started and before exporitng data from the old DB (between step 1 and 2)
Note: After GoldenGate 12.1.2, you can also use the start replicat with afterCSN to atCSN to avoid handling collisions.
- Checke the lag and remove HANDLECOLLISIOINS after repliat catches up (no lag)
<--- Now, the new DB should be synced up with the old DB (Query Database)
Oracle GoldenGate allows you to setup query database with
- Low cost database such as MySQL, SQL Server, Oracle Database Standard Edition
- Low cost Big Data platform such as HDFS, HIVE
- Running on low cost operating system
- With subset of data just needed by the query application
- The impacts to the transaction database is minimum (nonintrusive, low impact)
- Optimize the reporting database using techniques including materialized view, query re-write, advanced compression, partitioning and online redefinition.
- Setup the database with lower standard for backup recovery and high availability