Oracle GoldenGate is a heterogeneous product and supports many different platforms and databases. It is an extensive software package for real-time integration and replication.
Oracle GoldenGate 12c brings extreme performance with simplified management and configuration, tighter integration with expanded heterogeneity, Oracle Database, enhanced security and support for cloud environments.
Recently we had a webinar on Oracle Goldengate 12c. It was a very interactive webinar and attended by more than 500 attendees. Below are some interesting queries from attendees with answers that are worth sharing:
Q1. What is Goldengate?
A1. Oracle Goldengate is a near real-time data replication tool and it replicates the data from source database to target database. Replication can be uni-directional, bi-directional or multi-directional and it can involve several sources and targets simultaneously.You can use goldengate for backup, hot standby, auditing, reporting, warehousing and load distribution etc.
Q2. We have around 90TB of production database which is a 6 node RAC and using active data guard on the remote site again with 6 nodes RAC.so they have primary 6 node RAC and on DR side also 6 node RAC with Active data guard. Currently, inactive data guard node, they want to do active-active mode using goldengate. so what should be the starting point for such switch? What would you recommend? What are the common issues?
Ans. In this scenario, It depends on what kind of requirement you are looking for. It would be unidirectional as per the query. So one of the major advantages of goldengate is the way goldengate works on stand-alone database, in the same way, goldengate works on RAC database. So solution related to goldengate will always remain same.Here database size is 90TB that is huge so here we need to consider some of the design considerations.On DR site which is Active data guard and you want to do in active-active mode, if you are connected the DR site and application that is also writing and you want to bring it back to the primary site then you should pick bi-directional.
Q3. What is the business requirement for bi-directional replication?
Ans. Let’s suppose you have two databases and two applications. So if they are within the data center, you might say you put an RAC. However if you have a mission-critical application that you want to run active-active across datacenters, that might one of the reason for bidirectional.
Q4. In bi-directional, how does capture and replicate process knows that whether it coming from the source or going to target?
Ans. You have a separate replicate process, one from A to B and second, replicate capture process from B to A. So these are two different processes, one from A to B and second is from B to A.
Q5. What if any transaction committed at the source, if it fails to replicate on target?
Ans. There are multiple ways to do this and one way will be to implement Real-time replication.
Q6. Can we use goldengate with EBS?
Ans. yes, we can but only three topologies are supported and that is:
Q7. We are using Oracle data guard for EBS. Can we use Goldengate instead of data guard?
Ans. Yes, you can and you will use unidirectional Topology to do the same.
Q8. What is the difference between DBAs and Apps DBAs?
Ans. DBA’s handle Database only whereas Apps DBA’s are one who also handles application tier with databases like EBS, Fusion Middleware or any other application.
Q9. Is Goldengate just for Oracle database?
Ans. No, it is for other databases as well like MySQL, SQL Server, IBM, SAP, JMS, BIG Data and Hadoop etc.
Q10. Can we use Oracle Goldengate for building DR site for EBS?
Ans. Yes, Absolutely we can do that.
Q11. Does Oracle Goldengate support MySQL?
Ans. Yes, It supports MySQL database.
Q12. Can we setup Alert for time lags on Goldengate for any issues?
Ans. Yes, it is possible. You can set up various kinds of Alerts like for instance, your processes are stopped and you want to send an alert, you can do that. If a lag crosses the threshold then an email alert should be generated, you can do that. If you want to generate a daily report of statistics between source and target, it is possible. There are multiple ways to do that like one way to write Unix script or setup alert in OEM etc.
Q13. Can we use single manager process for source and target?
Ans. There are three processes in Golden gate: Capture, Pump and delivery. Each server will have its own Goldengate instance. Every Goldengate instance has its own manager process which manages the resources of Oracle Goldengate components. so answer is No, you can’t use single manager process for both.
Q14. How is Goldengate better than CDC?
Ans. Goldengate is a CDC (Change Data Capture) tool itself. Earlier we use CDC which is now Golden Gate with many benefits and much expensive price.
Q15. How will Goldengate help in cloud?
Ans. In Data replication and migration to the cloud.
Q16. We are using linked server to transfer data from SQL server to Oracle database. Can we use Goldengate?
Ans. Yes, you can use Goldengate by referring the architecture.
Q17. What is trail file size for source and target database?
Ans. Trail file size can vary between the source and Target databases. There is no definitive size. By default, it is 500 MB. You can always reduce or increase the size. Maximum size you can give is 10 GB and the minimum is 100 MB.
Q18. Can source and Target database have different time zone?
Ans. Yes, you can have that but lag shown to you may differ in that scenario.
Q19. What is the difference between checkpoint and lag?
Ans. Checkpoint ensures the data integrity of your environment to ensure zero data loss and Lag is the time difference between which a record is getting committed at the source and it is being applied to target that time difference is known as lag.
Q20. Is checkpoint SCN based?
Ans. Yes, Checkpoint have SCN information as well Apart from other information.
Q21. What should be the average bandwidth between the source and target database?
Ans. There is no definitive answer but more good the network is, better it is. You can calculate it depending on the environment.
There were lot of queries like above in webinar and attendees enjoyed the session and so we 🙂
Are you having any queries in Oracle GoldenGate 12c?
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