When designing a highly-available MySQL architecture, having a proxy to route the traffic to the appropriate instances is crucial to achieve transparent (or almost) failovers/switchovers. ProxySQL, a popular open source, SQL-level proxy is a great choice for this, and even though an experimental clustering feature is available, we could follow a simpler active-passive approach too, based on Common Address Redundancy Protocol (CARP), which will also provide a highly available IP for the applications to connect.

Solution overview

As mentioned before, this setup relies on a shared IP configured through CARP on the two hosts that will be running ProxySQL. CARP configuration is outside the scope of this post but the steps are on available on the FreeBSD documentation.

We then need to make sure all ProxySQL configuration changes performed on the …

If you are using Galera replication, you know that schema changes may be a serious problem. With its current implementation, there is no way even a simple ALTER will be unobtrusive for live production traffic. It is a fact that with the default TOI alter method, Percona XtraDB Cluster (PXC) cluster suspends writes in order to execute the ALTER in the same order on all nodes.

For factual data structure changes, we have to adapt to the limitations, and either plan for a maintenance window, or use pt-online-schema-change, where interruptions should be very short. I suggest you be extra careful here, as normally you …

We already have seen how to gather overall MySQL server diagnostics information and how to trace a specific thread activity. Let’s go to more granular level this time ! What about tracing a specific statement. Has MySQL a built-in way to do that ?

The “ps_trace_statement_digest” introduced in MySQL 5.7 allow tracing a specific statement digest (As explained in the doc : The digesting process converts each SQL statement to normalized form (the statement digest) and computes a SHA-256 hash value (the digest hash value) from the normalized result.Normalization permits statements that are …

We’re in the process of upgrading our MySQL databases from v5.7 to v8.0; since one of the differences in v8.0 is that the default encoding changed from utf8 to utf8mb4, and we had the conversion in plan anyway, we anticipated it and performed it as preliminary step for the upgrade.

This post describes in depth the overall experience, including tooling and pitfalls, and related subjects.

Contents:

• Introduction
• Migration plan: overview and considerations
  • …

Real-time web/mobile application is becoming popular day by day. Services like Firebase and Pusher provides API’s and Services to develop effective real-time notification system for your mobile and web apps.

We are not going to use these Services in this post; instead, we will develop an application that pops up notification on a particular event – Say a new comment added on Post. For notification, we will use Chrome desktop notification and for real-time communication – Socket.io.

I have already covered desktop notification here and Socket.io tutorial here.

DOWNLOAD Prerequisites :

Level of the …

In my last blog post we have seen how we can easily collect general MySQL status information using the sys.diagnostics() procedure. What about a single session/thread ? Is there built-in way to easily trace a target thread/session activity (ex: transactions/ statements/stage/wait events) like using an oracle SQL trace ?

The procedure “ps_trace_thread()” introduced in MySQL 5.7 allow monitoring a specific thread. This procedure is based on Mark Leith work in his blog post A Big Bag of Epic Awesomeness. (I love the title :))

It will  captures as much information on the thread activity as possible depending on the actual …

Has MySQL a built-in way to easily take a look at the overall server status without the need to execute many different custom query or program ? Maybe something similar to an oracle AWR report ?

Starting with MySQL 5.7.9 and later we can use the SYS procedure “diagnostics()” for that which rely the information available on the PERFORMANCE_SCHEMA !

Let’s give it a try  by generating a HTML report for the currently running instance (starts an iteration every 30 seconds and runs for at most 60 seconds using the current Performance Schema settings ) :

mysql -u root -p -H -e"CALL sys.diagnostics(60, 30, 'current');" > ./current_instance_report.html

The report contain information such as :

Wait event :

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In this tutorial, you'll learn how to easily add a complete authentication system to your Django application with login, logout and password change and reset functionalities.

We'll be using Django with a MySQL database.

We'll also be using django-crispy-forms and Bootstrap 4 for styling the application UI.

Prerequisites

Let's start with the prerequisites for this tutorial. In order to follow the tutorial step by step, you'll need a few requirements, such as:

Basic knowledge of Python, Working knowledge of Django (django-admin.py and manage.py), A recent version of Python 3 installed on your system (the latest version is 3.7), MySQL database installed on your system.

We will be using pip and venv which are bundled as modules in recent versions of Python so you don't actually need to install them unless you are working with old versions.

If you are ready, lets go started!

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In this blog post, I’m going to show you how to test Kubernetes locally on OSX/macOS. Testing Kubernetes without having access to a cloud operator in a local lab is not as easy as it sounds. I’d like to share some of my experiences in this adventure. For those who have already experienced in Virtualbox & Vagrant combination, I can tell you that it doesn’t work. Since Kubernetes will require virtualization, setting another virtual environment within another VirtualBox has several issues. After trying to bring up a cluster for a day or two, I gave up my traditional lab and figured out that Kubernetes has an alternate solution called minikube.

Installation

If your OSX/macOS doesn’t have brew I strongly recommend installing …

Please join Percona’s Principal Support Engineer, Sveta Smirnova, as she presents MySQL Performance Schema in 1 hour on Thursday, March 21st, 2019, at 10:00 am PDT (UTC-7) / 1:00 pm EDT (UTC-4).

Register Now

MySQL 8.0 Performance Schema is a mature tool, used by humans and monitoring products. It was born in 2010 as “a feature for monitoring server execution at a low level.” The tool has grown over the years with performance fixes and DBA-faced features. In this webinar, I will give …