During previous months, I’ve had some time to satisfy my curiosity about databases in containers and I started to test a little bit MySQL in Kubernetes.
This is how it all began…

In January I had the chance to be trained on Kubernetes attending the Docker and Kubernetes essentials Workshop of dbi services. So I decided to prepare a session on this topic at our internal dbi xChange event. And as if by magic, at the same time, a customer asked for our support to migrate a MySQL database to their Kubernetes cluster.

In general, I would like to raise two points before going into …

During previous months, I’ve had some time to satisfy my curiosity about databases in containers and I started to test a little bit MySQL in Kubernetes.
This is how it all began…

In January I had the chance to be trained on Kubernetes attending the Docker and Kubernetes essentials Workshop of dbi services. So I decided to prepare a session on this topic at our internal dbi xChange event. And as if by magic, at the same time, a customer asked for our support to migrate a MySQL database to their Kubernetes cluster.

In general, I would like to raise two points before going into …

If you have worked with an RDBMS for some time, you will likely have come across the statement SELECT 1.

However, rarely is it correctly explained to engineers what the origin of SELECT 1 is, and why it’s useless and wasteful? A google search is not going to give you the response you would hope, these ranked responses are just as useless as the statement itself.

Bloat

Seeing a SELECT 1 confirms two things. First you are using a generic ORM framework, quote, and second, you have never optimized your SQL traffic patterns.

“Frameworks generally suck.
They CLAIM to improve the speed of development and abstract the need to know SQL.
The REALITY is the undocumented cost to sub-optimal performance, especially with data persistence.”

Connection Pooling

SELECT 1 comes from …

Today we are going to guide you on how to show all users in the MySQL users Database. A common ...

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The post MySQL SHOW USERS: List All Users in a MySQL Database appeared first on RoseHosting.

If you have received the “Your PHP installation appears to be missing the MySQL extension which Is required by WordPress” ...

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The post Your PHP installation appears to be missing the MySQL extension which Is required by WordPress appeared first on RoseHosting.

When you work with AWS Aurora you have limited admin privileges. There are some different grants for MySQL including SELECT INTO S3 and LOAD FROM S3 that replace the loss of functionality to SELECT INTO OUTFILE and mysqldump/mysqlimport using a delimited format. While I know and use lambda capabilities, I have never executed anything with INVOKE LAMDBA directly from the database.

This week I found out about INVOKE COMPREHEND (had to look that product up), and …

I learned this week that 30+ years of Relational Database Management System (RDBMS) experience still does not prepare yourself for the disappointment of working with organizations that use a RDBMS; MySQL specifically; have a released production product, have dozens to hundreds of developers, team leaders and architects, but do not know the importance of, nor use transactions. If I was to ask this when interviewing somebody that would work with a database and the response was it is not important, or not used these days it would be a hard fail.

To use a RDBMS is to understand a very simple principle, a foundation of a transactional system. It is called ACID. Atomicity, Consistency, Isolation, Durability.

In a …

As a data architect I always ensure that for any database schema change there a fully recoverable execution path.
I have generally advised to create a patch/revert process for every change.  For example, if a change adds a new column or index to a table, a revert script would remove the respective column or index.
The goal is to always have a defensive position for any changes. The concept is that simple, it is not complex.

In its simplest form I use the following directory and file structure.

/schema
    schema.sql
    /patch
        YYYYMMDDXX.sql     where XX,ZZ are sequential 2 digit numbers, e.g. 01,02
        YYYYMMDDZZ.sql
   /revert
       YYYYMMDDXX.sql   This is the same file name in the revert sub-directory.
       YYYYMMDDZZ.sql

At any commit or tag in configuration management it is possible to create a current copy of the schema, i.e. use schema.sql.
It is also possible to take the first …

In this tutorial, we will show you how to create a backup of MySQL databases on an Ubuntu 20.04 VPS, ...

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The post How to Create a Backup of MySQL Databases Using mysqldump on Ubuntu 20.04 appeared first on RoseHosting.

A common MySQL strategy to perform updates with accumulating functions is to employ user-defined variables, using the UPDATE [...] SET mycol = (@myvar := EXPRESSION(@myvar, mycol)) pattern.

This pattern though doesn’t play well with the optimizer (leading to non-deterministic behavior), so it has been deprecated. This left a sort of void, since the (relatively) sophisticated logic is now harder to reproduce, at least with the same simplicity.

In this article, I’ll have a look at two ways to apply such logic: using, canonically, window functions, and, a bit more creatively, using recursive CTEs.

• Requirements and background
• …