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  • Learning about Kubernetes: JDBC database connectivity to an Oracle database

    In the past few months I have spent some time trying to better understand Kubernetes and how application developers can make use of it in the context of the Oracle database. In this post I’m sharing what I learned along that way. Please be careful: this is very much a moving target, and I wouldn’t…

  • Ansible tips’n’tricks: provision multiple machines in parallel with Vagrant and Ansible

    Vagrant is a great tool that I’m regularly using for building playground environments on my laptop. I recently came across a slight inconvenience with Vagrant’s Virtualbox provider: occasionally I would like to spin up a Data Guard environment and provision both VMs in parallel to save time. Sadly you can’t bring up multiple machines in…

  • Ansible tips’n’tricks: testing and debugging Ansible scripts using Vagrant

    At last year’s UKOUG I presented about Vagrant and how to use this great piece of software to test and debug Ansible scripts easily. Back then in December I promised a write-up, but for various reasons only now got around to finishing it. Vagrant’s Ansible Provisioner Vagrant offers two different Ansible provisioners: “ansible” and “ansible_local”.…

  • Using dbca to create a physical standby database

    While investigating new options I discovered with dbca for the previous article I noticed that it’s now possible to use Oracle’s Database Creation Assistant (dbca) to create a physical standby database using the -createDuplicateDB flag. I wanted to know how easily this can be done on my Oracle 18.5.0 system. I have 2 VMs, server3…

  • dbca now makes it easy to configure OMF on file systems

    Up until – and including – Oracle 12.1 I always found it not-quite-so-straight-forward to create a new database using Database Creation Assistant (dbca) and configure it with Oracle Managed Files (OMF) on a file system in silent mode. I really like to use OMF in my lab databases as it saves me a lot of typing. I…

  • Ansible tips’n’tricks: understanding your Ansible configuration

    When writing automation scripts I tend to use a local Ansible configuration file. This has certain advantages for me, such as including it in a version control system (VCS). It also is a valid option for developers without access to the global configuration file installed by the package manager. And more convenient to use than…

  • Oracle Linux 7 and a new YUM configuration since January 2019

    For quite some time I used to have a configuration file /etc/yum.repos.d/public-yum-ol7.repo managing my package sources in lab VMs. Today I noticed that this configuration file is deprecated, and has been replaced by a new model. This is explained in the Oracle Linux 7 administrator guide and a few other sources I totally missed. I…

  • Building your own local Oracle Linux 7 Vagrant base box

    I have been talking about Vagrant for a long time and use it extensively on my Ubuntu-powered laptop. I am using Oracle Linux 7.6 for most of my lab builds, and I like to have specific tools such as collectl, perf, and many others available when the VM boots. I als like to stay in…

  • Making some more sense of direct path reads during primary key lookups

    After having published my first article of 2019 I have received feedback I felt like including. With a nod to @fritshoogland, @ChrisAntognini and @FranckPachot. In the previous post I showed you output of Tanel Poder’s ashtop.sql as proof that direct path reads can occur even if all you do is look up data by primary…

  • Making sense of direct path reads during primary key lookups

    I recently made an interesting observation while monitoring database performance on an Oracle Enterprise Edition system. While looking at some ASH data (for which you must be licensed appropriately!) I came across direct path reads attributed to a select statement performing a primary key lookup. At first, this didn’t make much sense to me, but…