You may have heard about the term “split brain”. What it is? How does it affect your clusters? In this blog post we will discuss what exactly it is, what danger it may pose to your database, how we can prevent it, and if everything goes wrong, how to recover from it.

Long gone are the days of single instances, nowadays almost all databases run in replication groups or clusters. This is great for high availability and scalability, but a distributed database introduces new dangers and limitations. One case which can be deadly is a network split. Imagine a cluster of multiple nodes which, due to network issues, was split in two parts. For obvious reasons (data consistency), both parts shouldn’t handle traffic at the same time as they are isolated from each other and data cannot be transferred between them. It is also wrong from the application point of view - even if, eventually, there would be a way to sync the data (although …

It gives us great pleasure to announce that the 7.6 release of MySQL Cluster is now ready for prime time.

MySQL Cluster is the distributed database combining linear scalability and high availability. It provides in-memory real-time access with transactional consistency across partitioned and distributed datasets designed for mission critical applications.…

Percona announces the GA release of Percona Server for MySQL 5.7.22-22 on on May 31, 2018. Download the latest version from the Percona web site or the Percona Software Repositories. You can also run Docker containers from the images in the Docker Hub repository.

Based on MySQL 5.7.22, including all the bug fixes in it, Percona Server for MySQL 5.7.22-22 is the current GA release in the Percona Server for MySQL 5.7 series. Percona …

A data lake is “…a method of storing data within a system or repository, in its natural format, that facilitates the collocation of data in various schemata and structural forms…”1. Many companies find value in using a data lake but aren’t clear that they need to properly plan for it and maintain it in order to prevent issues.

The idea of a data lake rose from the need to store data in a raw format that is accessible to a variety of applications and authorized users. Hadoop is often used to query the data, and the necessary structures for querying are created through the query tool (schema on read) rather than as part of the data design (schema on write). There are other tools available for analysis, and many cloud providers are actively developing additional options for creating …

The schema changes in production can cause lock at time and makes the slave to lag. It is more tedious and troublesome with PXC ( Galera ) cluster which can be made smoother with Percona online schema change.

Image Courtesy : Photo by Andrew Ruiz on Unsplash

Let us show you how to install MySQL on your CentOS 7 server. MySQL is a relational database management system ...

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Percona announces the release of Percona Server for MySQL 5.6.40-84.0 on May 30, 2018 (downloads are available here and from the Percona Software Repositories). Based on MySQL 5.6.40, including all the bug fixes in it, Percona Server for MySQL 5.6.40-84.0 is now the current GA release in the 5.6 series. All of Percona’s software is open-source and free.

New Features

• A new string variable version_suffix allows to change suffix for the Percona Server version string returned by the read-only version variable. …

MySQL’s InnoDB Cluster was released on Apr 12, 2017, with version 5.7 and is also included in MySQL version 8.0.

MySQL InnoDB cluster provides a complete high availability solution for MySQL. MySQL Shell includes AdminAPI which enables you to easily configure and administer a group of at least three MySQL server instances to function as an InnoDB cluster. Each MySQL server instance runs MySQL Group Replication, which provides the mechanism to replicate data within InnoDB clusters, with built-in failover. AdminAPI removes the need to work directly with Group Replication in InnoDB clusters, but for more information see Chapter 18, Group Replication which explains the details. MySQL Router can automatically configure itself based on the cluster you …

MySQL has had spatial indexes for many years, but they have all been Cartesian (X and Y coordinates) indexes. MySQL 8.0 adds support for geographic (latitude-longitude) indexes. In an earlier blog post, I described how the feature works. In this post, we’ll go into the details of how to upgrade from 5.7 to 8.0 if you have spatial indexes.…

In a recent post, my colleague and teammate Peter Sylvester explained how we could customize MySQL’s configuration when running it as a Docker container.

Today I want to show you how to debug a Dockerized MySQL process. Let me start by showing you how I am starting my test container:

[fipar@coltrane ~]$ sudo docker run --memory-swappiness=1 -p 3308:3306 --name=mysql1 -e MYSQL_ROOT_PASSWORD=password -d mysql/mysql-server:5.7
Unable to find image 'mysql/mysql-server:5.7' locally
Trying to pull repository docker.io/mysql/mysql-server ...
5.7: Pulling from docker.io/mysql/mysql-server
Digest: sha256:eb3aa08c047efcb3e6bfcc3a28b80a2ec8c67b4315712b26679b0b22320f0b4a
Status: Downloaded newer image for docker.io/mysql/mysql-server:5.7 …