Earlier in the year, I was working on an issue where one of my clients had reported a massive influx in connection on their hosts after enabling Percona Monitoring and Management (PMM). This was something I had not seen before and after researching for a couple of days I discovered that if you monitor a MySQL instance with PMM configured to collect table statistics, and if the tables that it’s gathering statistics from are Federated, it will generate a connection on the remote host for the Federated tables, one for each Federated table in the instance. Let’s go over the details and provide some examples so we can understand this a bit better.

First, I’ll offer a reminder that a Federated table is simply a table that you can put in your MySQL instance that is empty locally and uses a network connection to get the data from …

More and more people are requesting how they could connect to MySQL without using a password but using a SSL certificate. Known as X509. CA Certificate A CA certificate is a digital certificate issued by a certificate authority (CA). It’s used by clients to verify the SSL certificates sign by this CA. Such certificates is […]

More and more people are requesting how they could connect to MySQL without using a password but using a SSL certificate. Known as X509.

CA Certificate

A CA certificate is a digital certificate issued by a certificate authority (CA). It’s used by clients to verify the SSL certificates sign by this CA.

Such certificates is usually paid and needs to be manually installed with MySQL Server. But by default, MySQL generates a self-signed certificate and provides its own CA.

For obvious reason, I will use the certificates that have been auto-generated by MySQL on my system. However, for production, I encourage you to have a real CA signed certificate.

The CA certificate is called ca.pem and is located in MySQL’s datadir (/var/lib/mysql/ca.pem on Oracle Linux, RHEL, Fedora, CentOS, …).

In case you don’t know where your ca.pem is located, you can …

We have another packed issue of OpenLampTech for you this week. And, we have our first sponsor with a smashing deal to help you configure your MySQL servers with ease. Thank you Releem for partnering with OpenLampTech this week!

The Newsletter for PHP and MySQL Developers

Receive a copy of my ebook, “10 MySQL Tips For Everyone”, absolutely free when you subscribe to the OpenLampTech newsletter.

In OpenLampTech issue #54, we have content covering:

• SQL Wildcards
• PHP Magic Methods Explained
• Managing CSS in WordPress block themes
• WordPress as a Twitter alternative?
• And much much more

…

In this blog post, I will try to cover a few dump and data-loading utilities offered by MySQL Shell.

What is MySQL Shell?

It is a robust client and code editor for MySQL. In addition to having APIs for dealing with MySQL, MySQL Shell offers scripting capabilities for JavaScript and Python. It provides an AdminAPI to manage MySQL servers and create InnoDB Cluster and ReplicaSet deployments. It supports an X DevAPI to work on both SQL and NoSQL interfaces via the X Protocol. Finally, it provides utilities to make working with MySQL in Python and Javascript mode easier.

Now, let’s jump into some practical stuff and see what these tools offer us.

Dump Utility

In the dump utility, there are three tools: util.dumpInstance(), util.dumpSchemas(), and util.dumpTables () so let’s discuss them one by one. 

1.  “util.dumpInstance()” – This was introduced in MySQL Shell 8.0.21 and …

One thing I commonly hear when working with my clients is “I want to change my DDL strategy in order to avoid locking in my database! The last time I used the same old method I ended up in a metadata lock situation!”

I agree that metadata locks can be painful, but unfortunately, it’s completely unavoidable, and changing from one tool to another won’t help with this. That said, it’s still worth it to examine how metadata locks work and what the impact is for each of the common tools and processes. In doing so we will see that all these tools will require metadata locks, but knowing more about how they work and how the use locking can help us determine the right tool for your specific use case.

Any time you make a change to a table a metadata lock is needed to ensure consistency between the table itself and MySQL’s data dictionary. In order for MySQL to establish this lock it has to wait for any query against the table in …

What is dual password in MYSQL and how it works was already covered by my colleague Brian Sumpter in Using MySQL 8 Dual Passwords.

However, let me do a brief recap here about it.

Dual password is the MySQL mechanism that allows you to keep two passwords active at the same time. This feature is part of a more extended set of password management features implemented in MySQL 8 to enforce better security and secrets management, like:

• Internal Versus External Credentials Storage
• Password Expiration Policy
• Password Reuse Policy
• Password Verification-Required Policy
• Dual Password Support
• Random Password Generation
• Failed-Login Tracking and Temporary Account Locking

The most important and requested features are the password expiration and …

Vitess is a solution that allows you to infinitely scale MySQL while providing clients and apps with a single logical view of the fleet of MySQL instances comprising any number of Keyspaces and Shards. Vitess also provides the cluster and data management tools that make it possible to manage a massive cluster and perform complex workflows using VReplication, such as: Moving tables into Vitess or between keyspaces Resharding to adjust to changes in data size and load Materialized views and rollups for data analytics and data locality Online schema changes that are trackable, cancellable, revertible, and retryable Why a Diff Tool?

Now that OpenLampTech is one year old, I have a point to prove. That I can consistently provide the MySQL, PHP, and LAMP stack communities with a valuable newsletter publication. Challenge accepted. This week’s issue is full of great content so give it a read!

The Newsletter for PHP and MySQL Developers

Receive a copy of my ebook, “10 MySQL Tips For Everyone”, absolutely free when you subscribe to the OpenLampTech newsletter.

In OpenLampTech issue #53, we have some fantastic content covering:

• WordPress Hooks, actions, and filters
• MySQL performance tips
• SQL TRANSACTION and Isolation Levels
• Top Linux mistakes and how to avoid them
• And much more …

AlmaLinux doesn’t natively support MySQL Workbench but these notes will help you install it. The great news is that MySQL Workbench works perfectly once you’ve installed all the dependent libraries. It’ll look like the following:

Disclaimer of sorts:

AlmaLinux is an open-source, community-driven project that intends to fill the gap left by the demise of the CentOS stable release. AlmaLinux is a 1:1 binary compatible fork of RHEL® 9 and it is built by the AlmaLinux OS Foundation as a standalone, completely free OS. The AlmaLinux OS Foundation will support future RHEL® releases by updating AlmaLinux. Ongoing development efforts are governed by the members of the community.

You can download MySQL Workbench from the following website:

https://dev.mysql.com/downloads/workbench

When you open this page, select the Red Hat Enterprise Linux 9 / Oracle Linux 9 (x86, 64-bit), RPM Package from the dropdown …