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  • New Events for Data Guard and Synchronous Redo Transport in 12c (1)

    I may have said it before but I consider presenting and teaching a great way to expand one’s knowledge: first of all it requires me to really understand a subject. Secondly, when presenting, you get lots of interesting questions that can turn into blog posts like this one. Lately I have been asked about the…

  • Creating a RAC 12.1 Data Guard Physical Standby environment (4)

    In the previous three parts of this series a lot of preparation work, needed for the configuration of Data Guard, was performed. In this part of the mini-series they all come to fruition. Using the Data Guard broker a switchover operation will be performed. A couple of new features in 12c make this easier. According…

  • Creating a RAC 12.1 Data Guard Physical Standby environment (3)

    In the previous two parts of this series you read about my lab environment and the preparations on the network side as well as the database. In this part I’ll cover the database duplication. Again, this won’t be a short post … NOTE: As always, this is just a demonstration using VMs in my lab, based…

  • Creating a RAC 12.1 Data Guard Physical Standby environment (2)

    In the first part of this mini-series you saw me define the environment as well as creating a primary database. With that out of the way it’s time to think about the standby. Before the standby can be created, a few preparations are necessary both on the primary as well as the standby cluster. NOTE:…

  • Creating a RAC 12.1 Data Guard Physical Standby environment (1)

    I have just realised that the number of posts about RAC 12c Release 1 on this blog is rather too small. And since I’m a great fan of RAC this has to change :) In this mini-series I am going to share my notes about creating a Data Guard setup on my 2 node 12.1.0.2.161018…

  • GTT and Smart Scan – the importance of the append hint

    While writing the previous two posts about GTTs and Smart Scan, I stumbled across an interesting observation. When I started putting my thoughts to (virtual) paper, I thought it was going to be a short post. Well, it wasn’t to be, again. Anyway, you might find this interesting. Initial Situation If you read the previous…

  • Smart Scanning GTTs – what about Flash Cache?

    Continuing the example of the previous blog post (is it possible to Smart Scan GTTs?), I am investigating if Smart Scans against GTTs can benefit from Flash Cache, or “optimised reads”. The easiest way to see this in your session is to calculate the change in session counters based on v$mystat or v$sesstat. Other tools…

  • Little things worth knowing: Can I Smart Scan a Global Temporary Table?

    A question that has come up while preparing to deliver another Exadata Optimisation Class is whether you can offload queries against Global Temporary Tables (GTT) or not. There are subtle differences between heap tables and GTTs such as how statistics are handled and where they are stored that merit a little investigation. I have used…

  • Building an RPM for the Oracle database on Oracle Linux 7

    Thinking about automation a lot, especially in the context of cloud computing, I have decided to create a small series of related posts that hopefully help someone deploying environments in a fully automated way. As my colleague @fritshoogland has said many times: the only way to deploy database servers (or any other server for that…

  • Little things worth knowing: when a transient ASM disk failure cannot be fixed in time

    In the previous blog post I used libvirt and KVM in my lab environment to simulate a transient disk failure and how to recover from it. This post takes this example a step further: I am simulating another disk failure, but this time won’t pretend I can fix the issue and put it back. In…