The tables in PERFORMANCE_SCHEMA (P_S) are not actually tables. You should not think of them as tables, even if your SQL works on them. You should not JOIN them, and you should not GROUP or ORDER BY them.
These installation notes are mostly a note to myself, documenting the installation process of a Gitlab Omnibus Container in Docker, plus Gitlab Runners.
At work, I am in an ongoing discussion with a number of people on the Observability of Outliers. It started with the age-old question “How do I find slow queries in my application?” aka “What would I want from tooling to get that data and where should that tooling sit?”
I have been asked to document my home sensor network. Being married to a person with a background in web security sets boundary conditions:
Es gibt ein Interview mit Stefan Ramesohl vom Umweltministerium (des Bundes) in Netzpolitik.org: “Warum niemand weiß, wie viele Rechenzentren es in Europa gibt”. Im Wesentlichen hat das Umweltministerium angesagt, daß es auf europäischer Ebene Rechenzentren erfassen und katalogisieren will, um in einem zweiten Schritt den Energieverbrauch von Rechenzentren zu regulieren.
Sometimes things change in a way that is hard to put a finger on, but I am doing this MySQL thing since 3.23, and commercially since 2005, and the environment is changing. These days, when you talk to people in need of MySQL, the first thing you have to ask them is “Which MySQL”. And by that I do not mean a version number in the first place.
Sven Geggus trolled me. A bunch of nerds were speaking about what’s wrong with biking in Germany, and he wrote:
Ok, so the title is a bit of an exaggeration, I am about 80% done with the main games quests. Still, the shape and feel of the story is firmly established and it is fascinating. I have some 110 hours in “Assassins Creed: Origin”, and some 65 hours or so in “Assassins Creed: Odyssey”.
Back when I was still commuting to work in an office, in the far past, I used to be in the Spaces building in Vijzelgracht in Amsterdam, every day. Mark Wagenbuur of BicycleDutch has been there today, and tweeted:
At work, replication chains have a single primary database node, to which you write, and then multiple replicas, in multiple AZs.
Ich schrieb in einem Twitter Thread über Posix Dateisysteme vs. Object Stores:
Every once in a while there is the IT news article that kind of triggers me. This time it was “Object-Storage-Protokoll könnte Posix ablösen” in german computer news site Golem. The article speaks about mmap(), NVMEoF and object storage and how it could revolutionize or complete object storages, but does not link to an original article, names no persons and no paper. Also, what do these things - mmap, NVMEoF, object storage and Posix, even have in common? It is not explained anywhere in the article.
All over the Internet people are having trouble getting LOAD DATA and LOAD DATA LOCAL to work. Frankly, do not use them, and especially not the LOCAL variant. They are insecure, and even if you get them to work, they are limited and unlikely to do what you want. Write a small data load program as shown below.
This is an update and translation of a much older article, which I wrote in German Language back then. I was experimenting with importing the account statements from my German Sparkasse, which at that time were being made available as a CSV.
In Deleting data we have been looking at a process that loads data into MySQL, leveraging partitions to make it easier and faster to later get rid of the data again. For this, we created three processes, a data loader process, and two observers - one for creating partitions, and one for deleting them.
Completing the data lifecycle is often harder than originally expected: Deleting data can cost sometimes way more than inserting it in the first place. MySQL Partitions can offer a way out. We have an earlier post on the subject.
MySQL uses connection and config parameters from a number of possible sources. The easiest way to find out where it is looking for config files is to run
A question to the internal #DBA channel at work: »Is it possible to change a column type from BIGINT to VARCHAR ? Will the numbers be converted into a string version of the number or will be it a byte-wise transition that will screw the values?«
Iterating schemas over time is not an uncommon thing. Often requirements emerge only after you have data, and then directed action is possible. Consequently, working on existing data, and structuring and cleaning it up is a common task.
Bei der ARD ist man empört! Teslas Kameras: ARD rückt Datenschutzbedenken ins Licht. Will sagen, jemand hat älteren Personen gesteckt, daß ein selbstfahrendes Auto wenig überraschend Kameras braucht, um bei seiner bestimmungsgemäße Verwendung weniger ältere Personen überzumöllern.