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  • Experimenting with the ZFSSA’s snapshot capability using the simulator part 2

    In my last post I wrote down some notes about my experience while experimenting with the ZFSSA simulator. A simulator is a great way to get familiar with the user interface and general usability of a product. What I wanted to find out using the ZFSSA simulator was the answer to the question: “what happens…

  • Experimenting with the ZFSSA’s snapshot capability using the simulator

    Recently I have been asked how the Copy-on-Write cloning works on the ZFS Storage Appliance. More specifically, the question was about the “master” copy: did it have to be static or could it be rolled forward? What better than a test to work out how it works. Unfortunately I don’t have an actual system available…

  • Trouble with multiple SCAN listeners in 12c Release 1

    UPDATE 28-JUL-2016: the problem – as stated by Anil in the comments section – seems to be fixed. I applied the Proactive Bundle Patch 23273686 and OJVM patch 23177536 to the Grid and RDBMS home. After a successful execution of datapatch the errors in the CRSD agent log I reported in this post went away, and I…

  • TABLE ACCESS INMEMORY FULL – but there may be more

    While preparing to teach a class this week I have had the time to look into the In Memory (cost) option a bit closer. I noticed a few interesting things along the way and would like to share one of these here. Background One of the questions I was asking myself was: “What happens if I…

  • Little things worth knowing: automatic generation of extended statistics in 12c Part II

    In my last post I demonstrated an example how to use a PL/SQL package to monitor a workload in order to identify correlated columns. Such columns are good candidates for the creation of extended statistics since the optimiser does not assume that information stored in different columns may be related. Before starting my tests I…

  • Little things worth knowing: automatic generation of extended statistics in 12c

    When you are migrating to Oracle 12c I hope you might this post useful. I came across this feature when researching what’s new with Oracle 12c (and yes I still find lots of new ones I haven’t noticed before). This one is a bit hidden away in section 2.2.4.3 Automatic Column Group Detection of the 12c New…

  • Example of Full Transportable Export to create a 12c PDB

    The Cool Stuff Oracle has introduced a new way of transporting data from one platform to another in 12c. The new feature is called “Full Transportable Export”. This enhancement works from 11.2.0.3 and later and is a great way to move data, as it allows for an easy-to-use combination of Export Data Pump and Transportable Tablespaces.…

  • CloneDB in Oracle 12.1.0.2

    I personally really like CloneDB, a way to thin-clone an Oracle database over NFS. This can be quite interesting, and I wanted to update my blog for 12.1.0.2.3 (April PSU). Tim Hall has a good example for 11.2.0.2 and later with further references. My setup is as follows: server3 (Oracle Linux 7.1) uses Oracle Restart and…

  • Fixing a problem with the ASM spfile preventing RAC 12c from starting

    This is a little note to myself on how to fix a corrupt spfile in clustered ASM. I hope you find it useful, too. Let’s assume you made a change to the ASM (server) parameter file that causes an issue. You are most likely to notice this once CRS is restarted but parts of the…

  • Little things worth knowing: Data Guard Broker Setup changes in 12c

    One of the problems I have seen when deploying Data Guard for systems such as RAC One Node and policy managed databases was the static listener configuration you needed in 11.2. This has changed with 12c for the better if you are using Grid Infrastructure. http://docs.oracle.com/database/121/DGBKR/install.htm In the section about static listener registration a little…