The “DBMS” part of MySQL is fine – storage engines (especially with new kids on the block), replication, etc, but it really sucks at executing SQL.

I won’t even get into complex SQL that has complex data dependencies, will start with very basic tasks.

SELECT * FROM table WHERE indexed = "A" LIMIT 1

If multiple indexes can satisfy the query, MySQL will hit each of them at least twice – looking up first “A” and last “A” records. It will do that while planning the SQL execution. Once it comes up with a plan, it will go and hit the index it picked again, this time once. So, if you have two candidate indexes, you will have 5 index accesses at 4 positions.

How would a direct cursor access work? Single index hit. Want to simulate that in SQL? You can add a ‘FORCE INDEX’ hint, then only one …

In this post, I’ll review Docker multi-host network performance.

In a past post, I tested Docker network. The MySQL Server team provided their own results, which are in line with my observations.

For this set of tests, I wanted to focus more on Docker networking using multiple hosts. Mostly because when we set up a high availability (HA) environment (using Percona XtraDB Cluster, for example) the expectation is that instances are running on different hosts.

Another reason for this test is that Docker recently announced the 1.12 release, which supports Swarm Mode. Swarm Mode is quite interesting by …

Hi everyone, its been a while since the last release of Group Replication. During this period we have been working hard to improve the plugin and give you a better user experience. Focused on solving several existing bugs, address performance issues and improving user
experience we renamed some variables, introduced new ones and changed some of the plugin policies.…

We’ll show you, how to create a MySQL Database and User in cPanel. There are different ways to create a MySQL database and user. In one of our previous blog articles about MySQL database administration, we described how to create a new MySQL database and user through the command line which is pretty easy. If you have a Linux VPS with cPanel you can create a new MySQL database through the control panel with just few clicks of your mouse.cPanel is one of the most popular and widely used control panels. In this tutorial we will guide you through the […]

Take Percona’s database security downtime poll.

As Peter Zaitsev mentioned recently in his blog post on database support, the data breach costs can hit both your business reputation and your bottom line. Costs vary depending on the company size and market, but recent studies estimate direct costs ranging in average from $1.6M to 7.01M. Everyone agrees leaving rising security risks and costs unchecked is a recipe for disaster.

Reducing security-based outages doesn’t have a simple answer, but can be a combination of internal and external monitoring, support contracts, enhanced security systems, and a better understanding of …

This blog reports the results of Percona’s high availability poll.

High availability (HA) is always a hot topic. The reality is that if your data is not available, your customers cannot do business with you. In fact, estimates show the average cost of downtime is about $5K per minute. With an average outage taking 40 minutes to correct, you could be looking at a potential cost of $200K if your MySQL instance goes down. Whether your database is on premise, or in public or private clouds, it is critical that your database deployment does not have a potentially devastating single point of failure.

The results from Percona’s high availability poll responses are in:

Note: There is a poll embedded within this post, please visit the site to participate in this post's poll.

With over 700 …

Hi everyone! It has been some time since the last MySQL Group Replication labs release was out. But the team has not been sitting on its hands. As such, it is time for a new labs release with new features, bug fixes and improvements across the board.…

Dear MySQL users,

The MySQL Windows Experience Team is proud to announce the release of MySQL Notifier version 1.1.7.

MySQL Notifier enables developers and DBAs to easily monitor, start and stop all their MySQL database instances. It provides a familiar Microsoft SQL Server look and feel and integrates with MySQL Workbench.

MySQL Notifier is installed using the MySQL Installer for Windows.

The MySQL Installer for Windows comes in 2 versions

• Full (150 MB) which includes a complete set of MySQL products with their binaries included in the download
• Web (1.5 MB – a network install) which will just pull the MySQL Notifier over the web and install it when run.

You can …

Shlomi Noach from the the Github engineering team posted the release of a new tool for triggerless online schema migration with MySQL. Although it's mostly targeted at databases using a replication architecture, if you don’t have replicas, or do not wish to use them, you are still able to operate directly on the master. In spite of being a wonderful project and being used in production by

In this blog, I will provide answers to the Q & A for the “Introduction into storage engine troubleshooting” webinar.

First, I want to thank everybody for attending the July 14 webinar. The recording and slides for the webinar are available here. Below is the list of your questions that I wasn’t able to answer during the webinar, with responses:

Q: At which isolation level do 

pt-online-schema-change

 and 

pt-archive

  copy data from a table?

A: Both tools do not change the server’s default transaction isolation level. Use either

REPEATABLE READ

 or set …