MySQL 8.0 introduces many new features. We will have a look at the exciting histogram  feature in MySQL 8.0

Histogram:

What is Histogram?

In General, a histogram is an accurate representation of the distribution of numerical data. In MySQL, It will be useful to collect data distribution for a specific column.

What problem it solves?

In general DB Optimizer gives us the best execution plan, But the stats make the execution plan better and better .The data distribution of values in columns can make good impact in optimiser in case of column with less distinct values.

We will see an example of how it helps optimizer in some cases. 

I have used a production case. MySQL version is 8.0.15 installed in ubuntu 18.04 (32GB RAM,8 core) with optimal configuration. Let us try to optimise a …

Welcome to our new blog series Benefits of SQL Diagnostic Manager for MySQL (formerly Monyog). This series will discuss the features of SQL Diagnostic Manager for MySQL designed to enable organizations to scale their existing resources for database administration. This week, we focus on the challenges associated with MySQL and MariaDB database systems.

The MySQL and MariaDB database systems are rapidly becoming the de-facto choice for traditional enterprises as well as pioneering Web 2.0 companies. Webyog has been consistently delivering powerful tools exclusively on the MySQL and MariaDB platform for the last 15 years.

While the adoption rate of MySQL and MariaDB continues to grow in momentum, it poses some unique challenges for traditional database administrators and their organizations. Some of these challenges are:

• Find problematic SQL queries
• Analyze MySQL and MariaDB performance data …

MySQL 8.0 : Error Logging
Here I would like to explain, How MySQL 8.0 server can be configured to log diagnosis messages inside the error log file. 
Generally, the error log contains:

• A record for mysqld service startup and shutdown.
• Diagnostic messages such as errors, warnings, and notes during mysqld server startup, running or shut down. 
• A stack trace if mysqld exits abnormally. 
• mysqld_safe writes once it finds mysqld exists abnormally and mysqld_safe invoke/start mysqld. 

Error Log Component Configuration MySQL 8.0 uses the MySQL error log component architecture that performs log …

The Question Recently, a customer asked us:

Why would heavy disk IO cause the Tungsten Manager and not MySQL to be starved of resources?

For example, we saw the following in the Manager log file tmsvc.log:

2019/06/03 00:50:30 | Pinging the JVM took 29 seconds to respond.
2019/06/03 00:50:30 | Pinging the JVM took 25 seconds to respond.
2019/06/03 00:50:30 | Pinging the JVM took 21 seconds to respond.
2019/06/03 00:50:30 | Pinging the JVM took 16 seconds to respond.
2019/06/03 00:50:30 | Pinging the JVM took 12 seconds to respond.
2019/06/03 00:50:30 | Pinging the JVM took 8 seconds to respond.

The Answer Why a Java application might be slow or freezing

The answer is that if a filesystem is busy being written to by another process, the background I/O will cause the Java JVM garbage collection (GC) to pause.

This problem is not specific to Continuent Tungsten …

So MySQL's group replication came out with MySQL 5.7. Now that is has been out a little while people are starting to ask more about it.

• https://dev.mysql.com/doc/refman/8.0/en/group-replication.html
• https://dev.mysql.com/doc/refman/8.0/en/group-replication-deploying-in-single-primary-mode.html

Below is an example of how to set this up and a few pain point examples as I poked around with it.
I am using three different servers,

 Server CENTOSA


mysql> INSTALL PLUGIN group_replication SONAME 'group_replication.so';
Query OK, 0 rows affected (0.02 sec)

vi my.cnf
…

In this tutorial, you will learn to build your first REST API web application with Java 11, Spring 5 and Spring Boot 2.2. We'll also use NetBeans 11 as the IDE.

For quickly initializing our Spring Boot application, we'll use Spring Initializr.

In our example, we'll be using Spring MVC and an embedded Tomcat server to serve our application locally by inlcuding the Spring Web Starter as a dependency of our project.

Spring is an open source Java EE (Enterprise Edition) framework that makes developing Java EE applications less complex by providing support for a comprehensive infrastructure and allowing developers to build their applications from Plain Old Java Objects or POJOS. Spring relieves you from directly dealing with the underlying and complex APIs such as transaction, remote, JMX and JMS APIs.

Spring framework provides Dependency Injection and Inversion of Control out of the box which helps you avoid the …

In this tutorial, you will learn to build your first REST API web application with Java 11, Spring 5 and Spring Boot 2.2. We'll also use NetBeans 11 as the IDE.

For quickly initializing our Spring Boot application, we'll use Spring Initializr.

In our example, we'll be using Spring MVC and an embedded Tomcat server to serve our application locally by inlcuding the Spring Web Starter as a dependency of our project.

Spring is an open source Java EE (Enterprise Edition) framework that makes developing Java EE applications less complex by providing support for a comprehensive infrastructure and allowing developers to build their applications from Plain Old Java Objects or POJOS. Spring relieves you from directly dealing with the underlying and complex APIs such as transaction, remote, JMX and JMS APIs.

Spring framework provides Dependency Injection and Inversion of Control out of the box which helps you avoid the …

Overview The Skinny

In this blog post we will discuss how to use the Tungsten Connector keep-alive feature to ensure long-running MySQL & MariaDB/Percona Server client sessions stay connected in a Tungsten Cluster.

Agenda What’s Here?

• Briefly explore how the Tungsten Connector works
• Describe the Connector keep-alives – what are they and why do we use them?
• Discuss why the keep-alive feature is not available in Bridge mode and why
• Examine how to tune the keep-alive feature in the Tungsten Connector

Tungsten Connector: A Primer A Very Brief Summary

The Tungsten Connector is an intelligent MySQL database proxy located between the clients and the database servers, providing a single connection point, while routing queries to the …

Codership, the makers of Galera Cluster are proud to be sponsors at the second annual DataOps.Barcelona happening June 20-21 2019 at the World Trade Centre in Barcelona, Spain.

For an opening keynote, in the Auditorium from 9.30-10.30am see Colin Charles speak about What’s New in Galera Cluster 4. There are plenty of new features and it debuts in MariaDB Server 10.4, so expect to hear a lot about what is available. On day two, Colin will also speak about Running MySQL and MariaDB Server securely in 2019.

Our booth will have Vlad Alexandru manning it all the time, and we would love to talk to you about Galera Cluster, roadmaps, plans, as well as our support, training and consulting for Galera Cluster for MySQL as well as Percona XtraDB Cluster (PXC).

Galera Cluster will also be running a raffle, so drop …

We were pleased to sponsor the Percona Live Conference in Austin this year: many thanks to the Percona Team for organising a smooth conference yet again!

This is the recap of our week in Texas!

At The Conference

This year’s conference was the first one not taking place in Santa Clara, CA, but rather in Austin, TX. This turned out to be a nice choice by Percona, as it meant that open source database users who may not have travelled to California in the past, were attracted to the new location; and Austin being the new hot spot for (tech) companies at the moment, a lot of “locals” seemed to have made the choice to attend the conference. It was great to meet many new faces as a result.

As Diamond Sponsors of the conference we were of course present with a booth in the exhibition hall, as well as with three talks.

And while the hotel looked slightly dystopian at night, it was in fact a nice and …