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.
I have made changes to the RSS Feed of this blog:
We have had a look at how MySQL 8 handles JSON recently, but with all those JSON functions and expressions it is clear that many JSON accesses cannot be fast. To grab data from a JSON column, you will use a lot of $->>field expressions and similar, and without indexes nothing of this will be fast.
So this has turned into a small series, explaining how to work with MYSQL from a developers perspective. This post is intended as a directory for the individual articles. It will be amended and re-dated as necessary.
MySQL 8 provides solid support for the JSON data type. The manual has an overview of the data type, a JSON function reference, an an overview on generated column indexes, and explains multi-values indexes.
I had to upgrade my company issued MacBook pro to Catalina for fleet unity reasons. The upgrade left me with a folder Relocated Items in /Users/Shared/Desktop and a link to that prominently on my Desktop.
Ok, it’s “Dad Stories” Time (from Twitter). When my son was somewhat older than a year, he was learning to speak. He could already say “Mama” and “Papa”.
Question: Hey, I got a UNIQUE INDEX, but I can store multiple rows with the same value, NULL. That is surprising. Is that a bug?
For reasons that don’t need exploring at this juncture I tweeted
This is the updated and english version of some older posts of mine in German. It is likely still incomplete, and will need information added to match current MySQL, but hopefully it is already useful.
Melissa and Chris Bruntlett have been living in Vancouver close to the
station, and decided to do as many daily runs as possible without a car,
using public transport or bikes. In late 2015, early 2016 they did an
extended visit to the Netherlands which resulted in a changed world view
about what proper Urban Infrastructure can look like. Meanwhile they are
living with two kids near Delft, in the Netherlands.
A Wizard’s Guide To Defensive Baking
is a Yound Adult Coming-of-Age story about Mona. Mona works in her aunt’s
bakery, and also is a hedge wizard. Her talent is mostly limited to
influencing dough and baked goods, her familiar is a sourdough starter named
Bob.
Since we now know how to look at the state of locking in a live database, let’s look at what happens when we run a normal insert or update and an insert or update with foreign key relationships defined, and compare.
