Some of our Percona Support customers report performance degradation after a major MySQL upgrade, and there can be many different reasons for this. These days, the most common major upgrade is from MySQL 5.7 (which recently reached EOL) to 8.0, and I am going to emphasize one important case that affects many database instances. Range […]

We know that SQL statement compatibility can change with major database version upgrades and that you should adequately test for them. But what about minor version upgrades?

It is dangerous to assume that your existing SQL statements work with a minor update, especially when using an augmented version of an open-source database such as a cloud provider that may not be as transparent about all changes.

While I have always found reading the release notes an important step in architectural principles over the decades, many organizations skip over this principle and get caught off guard when there are no dedicated DBAs and architects in the engineering workforce.

Real-world examples of minor version upgrade issues

Here are two real-world situations common in the AWS RDS ecosystem using MySQL.

1. You are an organization that uses RDS Aurora MySQL for its production systems, and you upgrade one minor version …

MySQL warnings are an anti-pattern when it comes to maintaining data integrity. When the information retrieved from a database does not match what was entered, and this is not identified immediately, this can be permanently lost.

MySQL by default for several decades until the most recent versions enabled you to insert incorrect data, or insert data that was then truncated, or other patterns that resulted in failed data integrity. Very few applications considered handling warnings as errors, and there is a generation of software products that have never informed the developers that warnings were occurring.

The most simplest example is:

CREATE SCHEMA IF NOT EXISTS warnings;
USE warnings;

CREATE TABLE short_name(
  id INT UNSIGNED NOT NULL AUTO_INCREMENT,
  name VARCHAR(20) NOT NULL,
  PRIMARY KEY(id)
);

INSERT INTO short_name (name) VALUES ('This name is too long and will get truncated');
ERROR 1406 (22001): Data too long for …

This post was originally published in 2011 and was updated in October 2023.

I see this message on our forums, and I think it’s a great question: “Which version of Percona Server is currently recommended?” It’s really the same question as “Which version of MySQL is currently recommended?” In this blog, we cover everything you need to know about how to choose the right version of MySQL for your needs, as well as key information on the latest versions, 5.7 and 8.0.

Understanding MySQL Versions

MySQL versions play a pivotal role in database management, as each MySQL version represents a distinct release, encompassing enhancements, bug fixes, and new features that affect the performance, security, and functionality of the database and applications. Staying informed about MySQL version updates is vital for anyone tasked with managing databases, as it directly impacts the efficiency and reliability of data …

Upgrading to MySQL version 8.0 is a hot topic since version 5.7 is approaching the official end of life very soon. MySQL 5.7 EOL is set for the end of October 2023.

If you feel unprepared for the upgrade, consider post-EOL support from Percona. But it would be the worst if you proceeded with the upgrade in haste.

• Long database service downtime
• Some queries become slow
• Applications stop working due to incompatibilities
• Data loss

This is what can happen if MySQL’s major upgrade to 8.0 turns out not as you hoped for. Yes, it can be that serious, so do consider the major upgrade as an important project, not just a routine maintenance task! From my experience as a Support Engineer, I think the most frequent problem is query …

An inordinate amount of our Galera Cluster customer base is still using the MySQL 5.7 variant of Galera Cluster. Besides not being able to have access to all the new features of the Galera 4 library, MySQL 5.7 is rapidly reaching End of Life (EOL) status in October 2023. This is less than six months away, and it is also why we would like to focus on getting our users upgraded to MySQL 8.0 with Galera Cluster.

Firstly, MySQL 8 has been Generally Available (GA) since 19 April 2018. That is a whole five years, and you must by now, already know that there is a new release model, where there are new features included in minor releases. The release notes are a must read. Next, Codership released Galera Cluster 4 with MySQL 8 with MySQL 8.0.19, on …

Recently we had a question on getting your Galera Cluster upgraded from MySQL 5.7 to MySQL 8.0. While we have plenty of extensive documentation on Upgrading Galera Cluster, this blog covers the Linux example for a rolling major upgrade (the procedure is documented, but this is more extensive). So we will describe going from MySQL 5.7.23 to MySQL 8.0.28 on one node. We did this on CentOS 7.

Firstly, let’s start by disabling SELinux by executing setenforce 0.

We need to install the appropriate MySQL 5.7 binaries, so we can grab them from releases.galeracluster.com. Since we have decided on MySQL 5.7.23, we should get the packages from …

Recently we got a question about how one can perform a minor version upgrade of a Galera Cluster, and today we just want to say that it is reasonably straightforward. While upgrades are a feature of Galera Manager that we are most excited to see come soon, today, doing it manually on the command line is quite simple! In this post, we will go through upgrading a 9-node geographically spread cluster, from MySQL 8.0.23 to 8.0.26. We also have extensive documentation: Upgrading Galera Cluster.

We have 3 nodes each in Singapore, London and San Francisco, making the cluster comprise of a total of 9 nodes, as we can confirm by executing: show status like 'wsrep_cluster_size';.

Since we installed all this via the RPM package manager on CentOS 7 by adding the YUM repository to the …

Recently we upgrade our database cluster to version 8.x .

Read this PDF to get some  experience    MySQL_8.x_upgrade

I've made a short video that will give you tips and tricks to successfully upgrade to MySQL 8

The post Plan your MySQL upgrade first appeared on dasini.net - Diary of a MySQL expert.