The amount of transactions committed is an important information, but how could you return an accurate value?

This is a question I got from my colleague Ivan, he was challenging with global status values like COM_COMMIT or HANDLER_COMMIT, then checking in innodb_metrics… but this was not accurate.

In fact depending which storage engine you are using, if binary logs are enabled, if you rollback transactions, if you are using auto_commit, etc… all those parameters influence those values.

So the first question was “What metrics or else should we use ?”. In my opinion, the most accurate “counter” for transactions are the GTIDs.

And this is why I created yet another MySQL Shell plugin that does that calculation:

This plugin is available on my GitHub repository …

Wooohooo MySQL 8.0.22 has been released today !

As usual, this release contains contributions from our great Community and let me thanks all the contributors on behalf of the MySQL Team.

MySQL 8.0.22 includes contributions from Denis Yarkovoy, Gord Thomson, Andrey Turbanov, Javier Matos Odut, Kan Liyong, Xiaoyu Wang, Daniël van Eeden, Krunal Bauskar, Eric Beuque and Facebook.

Thank you all for your great contributions. MySQL is an Open Source project, GPL, and we accept contributions !

Here is the list of the contributions above:

• Update command.cs by Denis Yarkovoy
• …

This post was first published on Oracle MySQL Blog.

If you are running MySQL on premise, it’s maybe the right time to think about migrating your lovely MySQL database somewhere where the MySQL Team prepared a comfortable place for it to stay running and safe.

This awesome place is MySQL Database Service in OCI. For more information about what MDS is and what it provides, please check this blog from my colleague Airton Lastori.

One important word that should come to your mind when we talk about MDS is SECURITY !

Therefore, MDS endpoint can only be a private IP in OCI. This means you won’t be able to expose your MySQL …

During the MDS webinar on how to deploy WordPress on OCI using MDS (slides & video), I briefly explained how to deploy the full architecture on OCI using Resource Manager and Stacks.

The Stack for that architecture is now available on my github: https://github.com/lefred/oci-wordpress-mds/releases/tag/0.0.1

To deploy it, it’s very easy. In OCI’s Dashboard, go on “Resource Manager” and then choose “Stacks“:

Create a new stack and just drop the …

Today we will see how to use MySQL Database Service aka MDS with WordPress.

To achieve this easy task, we will use the architecture we already deployed in this article.

We have then two Compute Instances on OCI, 1 running WordPress (Apache and PHP) and one running MySQL 8.0.

The Plan

This is how we will proceed to migrate to MDS with minimal maintenance time, we will:

1. create a MDS instance
2. verify if the database is ready to act as replication source
3. dump the MySQL instance running on OCI for being migrated to MDS.
4. load the dump in MDS
5. create a user dedicated to the replication
6. create a replication channel on MDS (from OCI to MDS)
7. modify WordPress config to point to MDS

Create a MDS …

In a recent article, I explained how to test MySQL Database Service (aka MDS) on OCI without having to setup a VPN.

A VPN is the recommended way and of course using some man-in-the-middle exposing the MySQL Classic and X Protocol port is something you should absolutely avoid !

So, in this article we will see another way to test or use MDS without VPN but using a more secure option.

SSH

The solution uses a SSH tunnel between your machine (laptop, etc..) and OCI.

How does it work ?

We have a MDS instance (10.0.1.3), and a compute instance (10.0.0.2). The compute instance is in the public subnet and has a public IP assigned to it.

Then we open a SSH tunnel to the compute instance’s public IP that forward all traffic to a certain port on localhost (we will use 3406) …

Please note that this is not recommended for any production purpose, don’t expose MySQL traffic to the Internet !

MySQL Database Service is now available, take a look at this nice introduction video:

It is usually a very bad idea to expose a database on a public IP (MySQL or any other database ). MDS doesn’t allow you to implement such bad security practice.

The best way to use your MySQL instance is to use a VPN as I explained in this article.

However, this can be restrictive for a simple test. In this post I will illustrate how you can setup a MDS instance and test it without having to setup any kind of VPN. Of course I recommend you to use such practice only for testing …

If you plan for example to have a bastion host in the cloud to access all your MySQL servers and use only MySQL Shell, the first time you connect to one of the host, you will realize that MySQL Shell prompts for a password but doesn’t ask you to store it of not.

Example:

mysqlsh fred@192.168.5.94
Please provide the password for 'fred@192.168.5.94': ****
MySQL Shell 8.0.21
Copyright (c) 2016, 2020, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its affiliates.
Other names may be trademarks of their respective owners.
Type '\help' or '\?' for help; '\quit' to exit.
Creating a session to 'fred@192.168.5.94'
Fetching schema names for autocompletion… Press ^C to stop.
Your MySQL connection id is 16 (X protocol)
Server version: 8.0.21 MySQL Community Server - GPL
No default schema selected; type \use to set one.
MySQL 192.168.5.94:33060+ ssl JS >
Bye!

As you could see, no …

I wanted to be brave and I installed MySQL Group Replication manually…. it was painful !

Then I realized that managing those servers and especially deal with MySQL Routers was even more painful !

What are my options now ? Is there a solution or do I need to restart from scratch ?

Asking the answer is already answering it… and once again MySQL Shell at the rescue.

MySQL Group Replication

I’ve configured everything manually. I also loaded group_replication and clone plugins and finally after having bootstrapped my Group here is what I have:

mysql> select member_host, member_port port, member_state state, 
       member_role role, member_version version 
       from performance_schema.replication_group_members;
+-------------+------+--------+-----------+---------+
| member_host | port | state  | role      | version | …

This morning, a user asked in the MySQL Community Slack if somebody had an idea why the error log was filled up continuously with a warning messages like this one:

2020-07-24T06:54:00.877128Z 46 [Warning] [MY-013360] [Server] 
Plugin sha256_password reported: ''sha256_password' is deprecated and will be removed in 
a future release. Please use caching_sha2_password instead'

The context was that the user upgraded from MySQL 5.7 to MySQL 8.0 and changed the authentication plugin of all users to caching_sha2_password.

As the warning message was written to the error log almost twice per second, I suspected a monitoring tool. The user said, that no application, no monitoring was using this server yet.

Of course we verified that all users had the plugin changed.

This is important when helping people (friends, colleagues, …