ProxySQL will be taking part in the upcoming EsLibre, open source event on the 18th & 19th of September. The date also coincides with ‘Software Freedom Day’ which celebrates Free Software, all over the world.

ProxySQL’s Senior Developer, Javier Jaramango Fernandez, will be discussing ‘Introduction to ProxySQL’, focusing on the importance of limiting downtime as much as possible, as well as, the tools ProxySQL offers and how you can use them to improve your infrastructure.

The talk will focus on the introduction of ProxySQL as a project, its characteristics, and the basic topology for its use.
Real-time examples and how to use them will also be discussed, such as:

• Zero-downtime configuration changes – ProxySQL offers three configuration layers: memory, disk and runtime. Each of these layers can be configured dynamically, with …

These are the slides of the “Efficient Use Of Indexes In MySQL” talk we delivered on the SFMySQL Meetup.

This is an introductory talk for developers on MySQL indexes. In my opinion, it’s quite important to understand how InnoDB organizes data. If you know how MySQL accesses data, it’s easier to write optimal queries.

When working with queries, I imagine secondary indexes as a table with records sorted by secondary key fields. This is a powerful concept that helps to understand the MySQL logic. It’s also easy to understand complex optimizations like loose index scan.

For example, for index (last_name, rank) the secondary index table looks like:

Enjoy the slides!

…

As a Database Engineer in Mydbops. We tend to solve multiple complex problems for our esteemed customers. To control the System resources and scale up /down based on needed we are evaluating Dockers and Kubernetes.

Docker is a set of platform as a service products that uses OS-level virtualization to deliver software in packages called Containers. Containers are isolated from one another and bundle their own software, libraries and configuration files; they can communicate with each other through well-defined channels.It’s more lightweight than standard Containers and boots up in seconds.

Docker also is easy to use when you need a simple, single instance. What is great about Docker though is that it allows configuring multiple versions of MySQL.

Docker Installation:

Docker can be installed with yum repository or apt-get repository based on your linux …

Why Does InnoDB Need A Dictionary

An InnoDB dictionary is a set of internal tables InnoDB uses to maintain various information about user tables. It serves as API between a human and the database. While the humans refer to tables by their names, InnoDB works with integer identifiers. The dictionary stores correspondence between table name and index_id.

The dictionary tables are normal InnoDB tables, but they’re not visible to a user. However, some versions of MySQL provide read-only access to the dictionary in information_schema database.

The dictionary is stored in ibdata1. Root page of SYS_TABLES, for example, has id 8, so it’s the eighth page from the beginning of ibdata1.

The dictionary pages are in REDUNDANT format even if you use MySQL 5.6. I hope to write more about record formats in future posts. For now, it’s enough to mention that REDUNDANT is the oldest record format. It was available since 4.0 …

In a previous blog post on Data Consistency for RDS for MySQL, we presented a workaround to manage run pt-table-checksum on RDS instances. However, if your instance is running a MySQL 8.0.X version, there’s a simpler way to check data consistency.

Starting with 8.0.1, MySQL introduced something called “Dynamic Privileges” which is a solution to grant more granulated privileges to the users, instead of the almighty SUPER privilege.

So what was the issue with pt-table-checksum and RDS again? Since there’s no SUPER privileges for any user, there was no way for the tool to change the binlog_format to STATEMENT… but not anymore.

The solution when using 8.0 is …

One of the questions you often will be faced with operating a Linux-based system is managing memory budget. If a program uses more memory than available you may get swapping to happen, oftentimes with a terrible performance impact, or have Out of Memory (OOM) Killer activated, killing process altogether.

Before adjusting memory usage, either by configuration, optimization, or just managing the load, it helps to know how much memory a given program really uses.

If your system runs essentially a single user program (there is always a bunch of system processes) it is easy.  For example, if I run a dedicated MySQL server on a system with 128GB of RAM I can use “used” as a good proxy of what is used and “available” as what can still be used.

root@rocky:/mnt/data2/mysql# free -h …

Watch the replay of our Geo-Scale MySQL webinar: Guaranteed Global Game Access for Hundreds of Millions of Players Worldwide - Cloud-Based Active/Passive Tungsten MySQL Clusters @ Riot Games.

Tags:  Webinar MySQL use case tungsten clustering mysql cluster geo-scale geo-distributed MySQL Riot Games …

Building Java with K8S using MySQL MDS

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 …

I have made changes to the RSS Feed of this blog:

1. Each <item/> does now contain a container <tags/>, inside a sequence of <tag/> containers, with each posts tags.
2. There is now a second RSS feed for posts tagged #mysql, because of demand. You can find it at https://blog.koehntopp.info/feed_mysql.xml.

Example for the tags:

<channel>
        <title>Die wunderbare Welt von Isotopp</title>
        ...
        <item>
                <title>A post title</title>
                <link>https://blog.koehntopp.info/2020/09/...</link>
                <guid isPermalink="false">/2020/09/...</guid> …