Hi everyone, its been a while since the last release of Group Replication. During this period we have been working hard to improve the plugin and give you a better user experience. Focused on solving several existing bugs, address performance issues and improving user
experience we renamed some variables, introduced new ones and changed some of the plugin policies.…

Hi everyone! It has been some time since the last MySQL Group Replication labs release was out. But the team has not been sitting on its hands. As such, it is time for a new labs release with new features, bug fixes and improvements across the board.…

Most people know that you can use SHOW SLAVE STATUS to verify if a slave is running in MySQL. Most people also know that you need to check both Slave_IO_Running and Slave_SQL_Running.

View the code on Gist.

A few years ago, I responded to a question on dba.stackexchange.com on how to verify if a slave is running outside of SHOW SLAVE STATUS.

Prior to MySQL 5.7, you could get this information from SHOW GLOBAL STATUS:

View the code on Gist.

Keep in mind that certain versions of 5.1 …

Overview

When working with Amazon AWS Aurora, there are some steps to consider when trying to get data out of an active Aurora master into a slave, potentially into a EC2 instance or offsite in another data centre. Creating an external mysql to Aurora gives the option to move out of Aurora, or to have the flexibility to move data around as desired. With AWS RDS instances this task is pretty simple because you can do the following :

1. Create a read replica
2. Stop the slave process
3. Capture the positioning
4. Dump the database

With Aurora it’s a little trickier, because a read replica in Aurora has no slave process. All of the replication is handled on the back end and cannot be controlled. However, setting up an external slave can be done.

Amazon AWS Documentation

In …

This article discusses how to salvage a crashed pt-online-schema-change by leveraging pt-archiver and executing queries to ensure that the data gets accurately migrated. I will show you how to continue the data copy process, and how to safely close out the pt-online-schema-change via manual operations such as RENAME TABLE and DROP TRIGGER commands. The normal process to recover from a crashed pt-online-schema-change is to drop the triggers on your original table and drop the new table created by the script. Then you would restart pt-online-schema-change. In this case, this wasn’t possible.

A customer recently needed to add a primary key column to a very busy table (with around 200 million rows). The table only had a …

In this tutorial we will show you how to setup basic MySQL replication on two CentOS 7 servers, but the same steps should work on all RPM based systems. We will use two test CentOS 7 virtual servers for this tutorial with the following IP addresses: MASTER: 123.456.789.1 SLAVE: 123.456.789.2 Master Server: Login to the master server as user root ssh root@IP_Address and install MySQL server if it is not already installed yum install mysql-server mysql Start the MySQL server and enable it to start at boot time systemctl start mysql systemctl enable mysql Next, open the MySQL configuration file […]

I posted recently Lossless RBR for MySQL 8.0 about a concern I have about moving to minimal RBR in MySQL 8.0.  This seems to be the direction that Oracle is considering, but I am not sure it is a good idea as a default setting. I talked about a hypothetical new replication mode lossless RBR and also about … Continue reading The differences between IDEMPOTENT and AUTO-REPAIR mode

The post The differences between IDEMPOTENT and AUTO-REPAIR mode first appeared on Simon J Mudd's Blog.

In this blog post we’ll discuss pt-online-schema-change, and how to correctly use it.

Always use pt-osc?

Altering large tables can be still a problematic DBA task, even now after we’ve improved Online DDL features in MySQL 5.6 and 5.7. Some ALTER types are still not online, or sometimes just too expensive to execute on busy production master.

So in some cases, we may want to apply an

ALTER

 first on slaves, taking them out of traffic pool one by one and bringing them back after the

ALTER

 is done. In the end, we can promote one of the already altered slaves to be new master, so that the downtime/maintenance time is greatly minimized. The ex-master can be altered later, without affecting production. Of course, this method works best when the schema change is …

Lossless RBR TL/DR: There’s been talk of moving the next release of MySQL to minimal RBR: I’d like to suggest an alternative: lossless RBR For MySQL 5.8 there was talk / suggestions about moving to minimal RBR as the default configuration (http://mysqlserverteam.com/planning-the-defaults-for-mysql-5-8/).  I’m not comfortable with this because it means that by default you do not have … Continue reading Lossless RBR for MySQL 8.0?

The post Lossless RBR for MySQL 8.0? first appeared on Simon J Mudd's Blog.

A video session on "Intro to MySQL master slave Replication". Hope you enjoy it :)