MySQL replication setups are inevitably related to failovers. Unlike multi-master clusters like Galera, there is one single writer in a whole setup - the master. If the master fails, one of the slaves will have to take its role through the process of failover. Such process is tricky and potentially, it may cause data loss. It may happen, for example, if a slave is not up to date while it is promoted. The master may also die before it is able to transfer all binlog events to at least one of its slaves.

Different people have different takes on how to perform failover. It depends on personal preferences but also on requirements of the business. There are two main options - automated failover or manual failover.

Automated failover comes in very handy if you want your environment to run 24x7, and to recover quickly from any failures. Unfortunately, this may come at a cost - in more complex failure scenarios, automated failover may not …

It's not always obvious what makes one database type distinct from another. What are the most significant ways that Amazon Aurora is different from MySQL? Clear separators aren't always featured or widely known, but even slight variables between two databases can prove valuable in choosing which one is right for you and your organization.

In the case of Aurora, there are at least three interesting things that make it unique and that present opportunities for particular uses. (Thanks in advance to @saileshkrish for helping us stay in-the-know on what Aurora can do.)

Adaptive Thread Pool

wow pic.twitter.com/KeVY5VBEMS

— Preetam (@PreetamJinka) December 21, 2016

Aurora's thread pool …

In today’s blog, I will show an issue with seconds_behind_master that one of our clients faced when running slave_parallel_works > 0. We found out that the reported seconds_behind_master from SHOW SLAVE STATUS was lying. To be more specific, I’m talking about bugs #84415 and #1654091.

The Issue

MySQL will not report the correct slave lag if you have slave_parallel_workers> 0. Let’s show it in practice.

I’ll use MySQL Sandbox to speed up one master and two slaves on MySQL version …

When we do Galera Cluster consulting we always discuss with the customer if his software is Galera Cluster ready. This basically means: Can the software cope with the Galera Cluster specifics?

If it is a software product developed outside of the company we recommend to ask the software vendor if the software supports Galera Cluster or not.

We typically see 3 different answers:

• We do not know. Then they are at least honest.
• Yes we do support Galera Cluster. Then they hopefully know what they are talking about but you cannot be sure and should test carefully.
• No we do not. Then they most probably know what they are talking about.

If the software is developed in-house it becomes a bit more tricky because the responsibility for this statement has to be taken by …

Welcome to another post in the series of Percona Live featured tutorial speakers blogs! In these blogs, we’ll highlight some of the tutorial speakers that will be at this year’s Percona Live conference. We’ll also discuss how these tutorials can help you improve your database environment. Make sure to read to the end to get a special Percona Live 2017 registration bonus!

In this Percona Live featured tutorial, we’ll meet Frédéric Descamps, MySQL Community Manager at Oracle. Frédéric is probably better known in the community as “LeFred” (Twitter: @lefred)! His tutorial is …

In this blog post, we’ll look at Performance Schema benchmarks for OLTP Read/Write workloads.

I am in love with Performance Schema and talk a lot about it. Performance Schema is a revolutionary MySQL troubleshooting instrument, but earlier versions had performance issues. Many of these issues are fixed now, and the default options work quickly and …

SQL databases tend to be rigid.

If you have worked with them, you would agree that database design though it seems easier, is a lot trickier in practice. SQL databases believe in structure, that is why it's called structured query language.

On the other side of the horizon, we have the NoSQL databases, also called schema-less databases that encourage flexibility. In schema-less databases, there is no imposed structural restriction, only data to be saved.

Though every tool has it's use case, sometimes things call for a hybrid approach.

What if you could structure some parts of your database and leave others to be flexible?

MySQL version 5.7.8 introduces a JSON data type that allows you to accomplish that.

In this tutorial, you are going to learn.

1. How to design your database tables using …

A proxy layer is an important building block for any highly available database environment. HAProxy has been available for a long time, as a generic TCP load balancer. We later added support for MaxScale, an SQL-aware load balancer. We’re today happy to announce support for ProxySQL, which also belongs to the family of SQL-aware load balancers. We blogged about ProxySQL sometime back, in case you would like to read more about it.

As from ClusterControl 1.4, we now support deployment and configuration of ProxySQL. It is done from a simple wizard:

You need to pick a host on which ProxySQL will be installed, you can choose to install it on one of your existing hosts in your cluster or you can type in a new host.

In the next step, you need to pick username …

Please join Percona’s Jon Tobin, Director of Solution Engineering at Percona, and Rob Masson, Solutions Architect Manager at ScaleArc, on Thursday, January 26, 2017, at 9:00 am PST / 12:00 pm EST (UTC-8) for their webinar “Overcoming the Challenges of Databases in the Cloud.”

Enterprises enjoy the flexibility and simplified operations of using the cloud, but applying those advantages to database workloads has proven challenging. Resource contention, cross-region failover and elasticity at the data tier all introduce limitations. In addition, cloud providers support different services within their database offerings.

Jon and Rob’s webinar is a …

This release introduces a new major feature – ‘read-only’ connections – as well as Kerberos authentication support and a few bug fixes.

Changes as compared to MySQL GUI 12.3.3 include:

Features:

* Added an option for defining a connection as ‘read-only’.  There is a checkbox in the connection settings and when checked the title bar will inform user about the ‘read-only’ state. In ‘read-only’ state statements that write cannot be executed. For more details please see note at the bottom.
* Added support for the MariaDB auth_gssapi (Kerberos) plugin. This plugin is available with the latest 3.0 (alpha) Connector/C from MariaDB. But there seems to  be a huge popular demand for this already, and we have backported it to the 2.3 connector version we use in SQLyog.  Note that support …