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  • Do I really have to set resource limits for Oracle in systemd unit files?

    TL;DR: it is very much required to set resource limits in systemd unit files. If you’d like to learn more about potential directives to put into a unit file, please have a look at the earlier post I wrote for a more thorough explanation. I also wrote a short post about a potential unit file…

  • Installing perf on Ubuntu 20.04 LTS in Oracle Cloud Infrastructure

    This is a very short post with instructions on how to install perf on Ubunutu 20.04 LTS in Oracle Cloud Infrastructure (OCI). I created my VM using the Canonical-Ubuntu-20.04-Minimal-2021.06.14-0 image. Updating the image first The first thing I do with each image I spin up in the cloud is to update all the packages. By…

  • Using systemd to start an Oracle single instance database when booting

    I don’t work with systemd frequently enough to remember its syntax and other intricacies so I thought I’d just write down how to start an Oracle 19c single instance database via systemd on Oracle Linux 8.4. Primarily so I can look it up later when I need it, but isn’t that the reason many bloggers…

  • Geeking out on Linux: file descriptors and their open modes & flags

    While preparing my talk for the upcoming POUG 2021 conference I wanted to know which flags Oracle passes to open(2) when accessing a data file. A file needs to be opened before its contents can be accessed (no surprises here :). There are quite a few ways of opening a file, depending on whether you…

  • Shell limits, Oracle Single Instance, and systemd in Oracle Linux 8.4

    The more blog posts I write the harder it becomes to come up with a good title. So what is this post all about? In short, it’s about the implications of using systemd to start a single instance Oracle database in Oracle Linux and associated shell limits. In theory this should apply to Single Instance…

  • Automating Vagrant Box versioning

    The longer I work in IT the more I dislike repetitive processes. For example, when updating my Oracle Linux 8 Vagrant Base Box I repeat the same process over and over: Boot the VirtualBox (source) VM Enable port forwarding for SSH SSH to the VM to initiate the update via dnf update -y && reboot…

  • SQLcl autotrace is way more than “just” (SQL*Plus) autotrace

    As part of the research I did for the 2nd edition of our Exadata book I used session statistics quite heavily. Session statistics can provide additional insights in situations where the wait interface on its own doesn’t get you any further. On the command line, my tools of choice are either Tanel Poder’s excellent Session…

  • Installing instant clients on Oracle Linux 8 in Oracle Cloud Infrastructure

    I recently presented my views on upgrading to Oracle 19c to the DOAG community. As part of that I pointed out how easy it was to deploy the Instant Client on a VM using yum and dnf. I previously wrote about the installation of the Instant Client in an on-premises configuration. UPDATE 250220: the post…

  • Installation of Oracle Restful Data Services 20.4 without using SYSDBA

    It’s really hard to come up with good, concise, and short twitter-compatible blog titles, so let’s try with a few more words. What I’d like to share is how to install Oracle Restful Data Services (ORDS) v20.4 without having to connect to the database as SYSDBA. There are good reasons not to connect as SYSDBA,…

  • Connecting to a database using SQLcl, a wallet and the thin driver

    I have previously written about the use of SQLcl and using an Oracle wallet (aka secure external password store). In my previous article I used the JDBC oci driver. This is perfectly fine, but as it’s based on Oracle’s Call Interface, it requires client libraries to be present. This time I wanted to use the…