The latest from the MySQL community

We've recently made a change "in the background", adding an index to each of our release note documents. For an (ample) example, look at the MySQL 5.7 release notes' index page.

The index should make it a lot easier for users to spot (and track) changes of particular features throughout the versions of a MySQL release series (for example, MySQL 5.7 or 8.0).

Release note indexes are automatically updated as new changelogs are created; this is one of the advantages of our highly automated documentation infrastructure -- keeping indexes updated manually would simply not be possible.

Update (2017-07-03): New screenshot, reflecting more readable / less cluttered links to individual release notes.

This blog post looks at SSL connections and how they work in MySQL 5.7.

Recently I was working on an SSL implementation with MySQL 5.7, and I made some interesting discoveries. I realized I could connect to the MySQL server without specifying the SSL keys on the client side, and the connection is still secured by SSL. I was confused and I did not understand what was happening.

In this blog post, I am going to show you why SSL works in MySQL 5.7, and it worked previously in MySQL 5.6.

Let’s start with an introduction of how SSL worked in 5.6.

SSL in MySQL 5.6

The documentation for SSL in MySQL 5.6 is quite detailed, and it explains how SSL works. But first let’s make one thing …

Next up in the "quick look" series is a discussion of connection management best practices and the memory usage implications of idle connections in Aurora and MySQL. I'll also throw in some notes on how to configure your connection pools to avoid unpleasant surprises.

Thread handling in Aurora vs MySQL Community MySQL editions use "one-thread-per-connection" approach to thread handling. It means that each individual user connection receives a dedicated OS thread within the mysqld process. This comes with issues, such as: 

• Relatively high memory usage with large number of user connections, even if the connections are completely idle.
• Higher internal server contention and context switching overhead when working with thousands of user connections.

To avoid such issues, some servers support a thread pool approach. Examples include Percona Server and Amazon Aurora.

…

For the impatient:

# echo -e "deb http://repo.mysql.com/apt/debian/ stretch mysql-5.7\ndeb-src http://repo.mysql.com/apt/debian/ stretch mysql-5.7" > /etc/apt/sources.list.d/mysql.list
# wget -O /tmp/RPM-GPG-KEY-mysql https://repo.mysql.com/RPM-GPG-KEY-mysql
# apt-key add /tmp/RPM-GPG-KEY-mysql
# apt update
# apt install mysql-server

In the latest stable version of Debian, if you ask to install mysql-server, you now get installed mariadb automatically, with no (evident) way of installing Oracle’s MySQL. Any major version upgrade has to be done carefully (not only for MariaDB, but also for MySQL and Postgres), and I bet that a MySQL 5.5 to MariaDB 10.1 will cause a huge confusion. Not only it will fail user expectations, I think this will cause large issues now that MariaDB has chosen to become a “hard” fork, and become incompatible in many ways with MySQL. Not only the server upgrade will cause user struggle, the connector is …

In this blog, we’ll look at different MySQL high availability options.

The dynamic MySQL ecosystem is rapidly evolving many technologies built around MySQL. This is especially true for the technologies involved with the high availability (HA) aspects of MySQL. When I joined Percona back in 2009, some of these HA technologies were very popular – but have since been almost forgotten. During the same interval, new technologies have emerged. In order to give some perspective to the reader, and hopefully help to make better choices, I’ll review the MySQL HA landscape as it is in 2017. This review will be in three parts. The first part (this post) will cover the technologies that have been around for a long time: the elders. The second part will focus on the technologies that are very popular today: the adults. Finally, the last part will try to extrapolate which technologies could become popular in the upcoming years: the …

This blog post looks at the recent MariaDB Server 10.2 GA release.

Congratulations to the MariaDB Foundation for releasing a generally available (GA) stable version of MariaDB Server 10.2! We’ll definitely spend the next few weeks talking about MariaDB Server 10.2, but here’s a quick overview in the meantime. Keep in mind that when thinking about compatibility, this is meant to be the equivalent of MySQL 5.7 (GA: October 21, 2015, with Percona Server for MySQL 5.7 GA available February 23, 2016).

…

Opps!I admit my JavaScript skills are rusty and dusty. Plus I am new to Node.JS. So yesterdays blog drew some very helpful comments from two of MySQL's best. Johannes Schlüter and Rui Quelhas let me know there was a better way to code the example. Much thanks to them. Better Example

// Simple example to grap one record and print it
const mysqlx = require('@mysql/xdevapi');
const options = {
  host: 'localhost',
  port: 33060, // should be a number
  dbUser: 'root',
  dbPassword: 'Hell0Dave!'
};

mysqlx
  .getSession(options)
  .then (session => {
  var schema = session.getSchema('world_x');

//equivilent of SELECT doc FROM countryinfo where _id = 'USA'
  var coll = schema.getCollection('countryinfo');
  var query = "$._id == 'USA'";

      // Print doc 
     return Promise.all([
       coll.find(query).execute(function (doc) {
       console.log(doc); …

MySQL's new NoSQL database is quite a big change for all used to using a SQL speaking relational database. The Document Store makes use of the new MySQL Shell, the new X Protocol, and the new X Devapi to provide a NoSQL document storage service. This provides a way for developers to have a schema-less, NoSQL data store to build services and applications is a quick fashion without having to design a schema, normalize data, develop queries in SQL, or any of the rest of the overhead needed to create a relational databases. Behind the scenes and invisible to the developer is that the schema-less data is stores in a JSON type column in a MySQL instance.

Please note that I am using JavaScript Mode (instead of SQL or Python) for these examples. No special reason.

First Step The new MySQL Shell is a separate install from the server software. Once installed it will provide the ability to use MySQL as a document store. …

In this post we’ll review how MySQL triggers can affect queries.

Contrary to what the documentation states, we can activate triggers even while operating on views:

https://dev.mysql.com/doc/refman/5.7/en/triggers.html

Important: MySQL triggers activate only for changes made to tables by SQL statements. They do not activate for changes in views, nor by changes to tables made by APIs that do not transmit SQL statements to the MySQL server.

Be on the lookout if you use and depend on triggers, since it’s not the case for updatable views! We have reported a documentation bug for this but figured it wouldn’t hurt to mention this as a short blog post, too. The link to the bug in question is here:

In the last couple of blogs, we covered how to run a Galera Cluster on Docker, whether on standalone Docker or on multi-host Docker Swarm with overlay network. In this blog post, we’ll look into running Galera Cluster on Kubernetes, an orchestration tool to run containers at scale. Some parts are different, such as how the application should connect to the cluster, how Kubernetes handles failover and how the load balancing works in Kubernetes.

Kubernetes vs Docker Swarm

Our ultimate target is to ensure Galera Cluster runs reliably in a container environment. We previously covered Docker Swarm, and it turned out that running Galera Cluster on it has a number of blockers, which prevent it from being production ready. Our journey now …