Oracle

Is OpenLogReplicator ready for production usage?

This is the question I hear very often. I think many people would like to hear a straight answer for this question. The reality is not possible to give a good answer. You might be surprised but, even though version 1.0 is not yet released, OpenLogReplicator is already used in production systems. Yet might be not feasible for everybody to use.

Oracle database log-based CDC on Raspberry PI

The task here is just to run native replication solution directly on Raspberry PI hardware. No emulators, no workarounds, no cheating. Let’s find out what is the redo log processing speed. The key to this approach is using OpenLogReplicator as CDC engine and it’s offline mode. With this mode you can read redo logs without …

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Supplemental logging – how much space does it require?

Oracle at some point of decided that users might want to replicate the changes from the database to other targets. What they noticed, that the architecture of the database did not allow easy replication since the redo log did not contain information that would allow to identify the exact row, that has been modified. The …

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OpenLogReplicator – replication latency

Replication latency is one of the key indicators of good replication. When I started working on OpenLogReplicator one of my key tasks was to keep the latency as low as possible. What does that mean? When a client commits a transaction and the database confirms that the transaction is committed – it means that the …

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OpenLogReplicator – logdump functionality

A side product of OpenLogReplicator is the ability to create logs which are in a very simular form as the logdump command from Oracle database. To create such dump you need to configure parameter in the OpenLogReplicator CFG file. There are 2 allowed values: create classic ‘logdump’ output create classic ‘logdump’ output enhanced with interpretation …

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OpenLogReplicator – first log-based open source Oracle to Kafka CDC replication

I have figured out that writing about somebody else’s software is boring. Why not create your own. So here it is: All code GPL v.3 Just C++ code – absolutely no Java/Python or any other interpreted language Purely reading Oracle Redo Log from disk – zero additional load to the database instance High performance architecture …

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Oracle GoldenGate data filtering with WHERE and FILTER parameters the right way

One of the most trivial tasks for data replication is to define a replica of the table with just a subset of the rows from the source table. For example we would like just to replicate the ACCOUNTS table with some type (one column has some defined value). If you want to replicate that using …

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Oracle GoldenGate point in time source database recovery

Even though you would like to secure the database from any disaster with HA, still it might happen that the database gets corrupted and a recovery from backup is needed to recover the database. In a critical scenario you might need to use Point In Time Recovery (PITR). Let’s focus on a scenario when the …

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Oracle GoldenGate Coordinated Replicat – is it a fully transactional replication?

Oracle GoldenGate till version 11.2 could only work serially. The only way of creating parallel replication and speeding up the apply process was to create multiple Replicat processes. In version 12.1 there was a new option available: the Coordinated Replicat. It is often misunderstood as a way of speeding up transactional replication. But … is …

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