We are well aware that MySQL Group Replication is one of the faster evolving clustering Technology for MySQL. Flow Control plays a key factor in Group Replication performance and data integrity . In this blog I am going to explain about the Flow Control mechanism and How it has evolved in MySQL 8 ?

What is Flow Control ?

MySQL Group Replication / Native Async replication needs binary logs to get the data flow across the servers.

What makes the difference ?

In the MySQL Group Replication we are trying to achieve the Synchronous replication with the help of a Flow Control mechanism and transaction acknowledgments ( certification ).

Without Flow Control, the MySQL Group Replication is asynchronous replication ? Yes, consistency is lost.

Lets us consider

We have three nodes ( GR1, GR2, GR3 ) . Gr1 is the master and and other two servers ( GR2, GR3 ) are the …

There was an option during the Fedora 30 Workstation installation to add the Apache Web Server, but you need to set it to start automatically. Unfortunately, there was no option to install PHP, which I thought odd because of how many web developers learn the trade first on PHP with a LAMP (Linux, Apache, MySQL, Perl/PHP/Python) stack. You see how to fix that shortcoming in this post and how to install and test PHP, mysqli, and pdo to support MySQL 8.

Before you do that make sure you install MySQL 8. You can find my prior blog post on that here.

You set Apache to start automatically, on the next boot of the operating system, with the following command:

chkconfig httpd on

It creates a symbolic link:

Created symlink /etc/systemd/system/multi-user.target.wants/httpd.service → …

While updating my class image to Fedora 30, I noticed that it installed the Akonadi Server. The documentation on the Akonadi server lacked some straightforward documentation. It also offered a bundled set of software that limited how to approach MySQL development.

So, I removed all those packages with the following syntax:

dnf remove `rpm -qa | grep akonadi`

Display detailed console log →

Dependencies resolved.
=============================================================================
 Package                          Arch    Version            Repo       Size
=============================================================================
Removing:
 akonadi-import-wizard            x86_64  19.04.2-1.fc30     @updates  2.8 M
 kf5-akonadi-calendar             x86_64  19.04.2-1.fc30     @updates  2.6 M
 kf5-akonadi-contacts             x86_64  19.04.2-1.fc30     @updates  3.3 M
 kf5-akonadi-mime …

Partnering to participate knowledge sharing for the community of Database Administrators.

In continuation to the community contribution with knowledge gained out of experience and networking, Mydbops IT Solutions, conducted its 4th Database Meetup on Saturday, 3rd of August, 2019. Here was the first time, that we had changed our venue. With the like-minded sponsor in M/s.Zenefits Technologies India Pvt. Ltd. They played a role of a perfect host for all of us as attendees. Their venue was a perfectly equipped to suit the knowledge sharing exercise.

Key note by Mr.Ramesh Aithal, Head of Engineering at Zenefits was build on statistics, of how the Industry is taking shape and the galore of opportunities in the coming days. The attendees from multiple companies were a great …

Mydbops continues with its commitment to the open source community comprising of Database Administrators. After the successful conduct of three meet-ups in the past, we are now stepping ahead on to the 4th edition of Mydbops Database meet-up.

First time, we are going to the new venue, thanks to the kind people of Zenefits Technologies India Pvt.Ltd., It is a real pleasure to be hosted by the like-minded organisation in the city of Bangalore, scheduled on Saturday, 3rd of August, 2019 at Zenefits Office.

In the past three editions, the focus was on the latest and hands-on topics by the selected speakers from the DBA World. This focus gets sharper this time as well. The topics for the 4 th Mydbops Database Meetup are:

InnoDB scalability improvements in MySQL 8.0 – Mr. Karthik P R, Founder / CEO of Mydbops, a MIT Masters …

In this blog, we will see how to do a flashback recovery or rolling back the data in MariaDB, MySQL and Percona.

As we know the saying  “All humans make mistakes”, following that in Database environment the data modified accidentally can bring havoc to any organisations.

Recover the lost data

• The data can be recovered from the latest full backup or incremental backup when data size is huge it could take hours to restore it.
• From backup of Binlogs.
• Data can also be recovered from delayed slaves, this case would be helpful when the mistake is found immediately, within the period of delay.

We can use anyone of the above ways or other that can help to recover the lost data, but what really matters is, What is the …

MySQL User camp is one of the prestigious MySQL meetup happening in India for the past 6 years. Mydbops DBA’s PonSuresh and Vignesh has presented about the “JSON functions and their improvements in MySQL 8.0” at MySQL User Camp Bangalore on 13-02-2019.

JSON has been more improved a lot in MySQL 8.0 and improvements in LOB storage of MySQL boost it performance further. This presentation covers the JSON performance enhancements in MySQL 8.0 with its basic functions.

JSON improvements in MySQL 8.0 from Mydbops

After installing MySQL 5.7.22 and PHP 7.1.17 on Fedora 27, you need to install the mysqli library. You need to verify if the mysqli library is installed. You can do that with the following mysqli_check.php program:

Check mysqli Install<?php if (!function_exists('mysqli_init') && !extension_loaded('mysqli')) {
    print 'mysqli not installed.'; }
  else {
    print 'mysqli installed.'; }
?>

You test preceding PHP program with the following URL in a browser:

http://localhost/mysqli_check.php

If the mysqli program isn’t installed, you can install it as follows by opening the yum interactive shell:

[root@localhost html]# yum shell
Last metadata expiration check: 1:26:46 ago on Wed 22 Aug 2018 08:05:50 PM MDT.
> remove php-mysql
No match for argument: php-mysql
Error: No packages marked for removal.
> install php-mysqlnd
> …

The UTF-8 is a variable-length encoding.  In the case of UTF-8, it means that storing one code point requires one to four bytes. But, In MySQL’s encoding called “utf8” only stores a maximum of three bytes per code point. In the modern web / mobile applications, we have to support for storing not only language characters but also symbols and emojis, Let me show you below some very weird issues faced using MySQL “utf8” :

mysql> SET NAMES utf8; # just to emphasize that the connection charset is set to `utf8`
Query OK, 0 rows affected (0.00 sec)

mysql> UPDATE custfeeds.reactions SET reacted = 'super like ' WHERE id = 13015;
Query OK, 1 row affected, 1 warning (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 1

mysql> SELECT reactions FROM custfeeds.reactions WHERE id = 13015;
+-------------+
| reactions   |
+-------------+
| super liked |
+-------------+
1 row in set (0.00 sec)


mysql> SHOW WARNINGS; …

While updating my class image to Fedora 27, I noticed that it installed the Akonadi Server. The documentation on the Akonadi server lacked some straightforward documentation. It also offered a bundled set of software that limited how to approach MySQL development.

So, I removed all those packages with the following syntax:

dnf remove `rpm -qa | grep akonadi`

After removing those Akonadi packages, I installed the MySQL Community Edition from the Fedora repo with this syntax:

yum install -y community-mysql*

Having installed MySQL Community Edition, I started the service with this command:

sudo service mysql start

Then, I ran the mysql_secure_installation script to secure the installation:

mysql_secure_installation

The script set the root user’s password, remove the anonymous user, disallow remote root login, and …