To reduce the backup size, save storage space, and speed up the backup and restore process, you can compress a backup with Percona XtraBackup. The XtraBackup --compress option makes XtraBackup compress all output data, including the transaction log file and metadata files, with one of the supported compression …

This blog describes how to configure systemd for multiple instances of MySQL. With package installations of MySQL using YUM or APT, it’s easy to manage MySQL with systemctl, but how will you manage it when you install from the generic binaries?

Here, we will configure multiple MySQL instances from the generic binaries and manage them using systemd.

Why do you need multiple instances on the same server?

We will do that, but why would you need multiple instances on the same host in the first place? Why not just create another database on the same instance? In some cases, you will need multiple instances on the host. 

1. You can have a host with two or three instances configured as a delayed replica of the source server with SQL Delay of, let’s say, 24hr, 12hr, and 6/3hrs.
2. Backup testing. You can run multiple instances on a server to test your backups with the correct version and configs. …

This blog post will cover the basic setup of the InnoDB ClusterSet environment, which provides disaster tolerance for InnoDB Cluster deployments by associating a primary InnoDB Cluster with one or more replicas in alternate locations/different data centers. InnoDB ClusterSet automatically manages replication from the primary cluster to the replica clusters via a specific ClusterSet Async replication channel. If the primary cluster becomes inaccessible due to a loss of network connectivity or a data center issue, you can make a replica cluster active in its place.

Now, let’s see in detail how exactly we can configure the topology.

We have used the sandbox environment available via MySQLShell utility for this setup.

Environment

Cluster1:
         127.0.0.1:3308
         127.0.0.1:3309
         127.0.0.1:3310

Cluster2:
         127.0.0.1:3311
         127.0.0.1:3312
         127.0.0.1:3313

Router: …

This blog was originally published in February 2017 and was updated in September 2023.

In this blog post, I provide an in-depth introduction to MySQL Replication, answering what it is, how it works, its benefits and challenges, as well as reviewing some of the MySQL replication concepts that are part of the MySQL environment (and Percona Server for MySQL specifically). I will finish by also clarifying some of the common misconceptions people have about replication and how Percona can help.

Since I’ve been working on the Solution Engineering team, I’ve noticed that – although information is plentiful – replication is often misunderstood or incompletely understood.

What is MySQL Replication?

MySQL replication is …

MySQL 8.0.34 brings us a new password validation parameter. Using this, we can control the minimum number of characters in a password that a user must change before validate_password accepts a new password for the user’s account.

In this blog, I offer a few scenarios showing how the parameter validate_password.changed_characters_percentage affects user password changes.

Requirement

To make this work, we should enable the “Password Verification-Required Policy” (introduced in MySQL 8.0.13). We can allow it to GLOBALLY by using the parameter “password_require_current” or by specifying  “PASSWORD REQUIRE CURRENT” while creating or altering the user. This topic was already explained very well by Brain Sumpter in his post, …

MySQL 8 brought a significant architectural transformation by replacing the traditional MyISAM-based system tables with the Transaction Data Dictionary (TDD), a more efficient and reliable approach. This upgrade has vastly improved the management and storage of metadata, resulting in better reliability and scalability for various database objects. In this blog post, we will explore the intricacies of MySQL 8’s Transaction Data Dictionary, its advantages, and its real-life application using practical examples.

At the core of MySQL 8’s InnoDB storage engine, the Transaction Data Dictionary (TDD) plays a fundamental role in storing crucial metadata concerning database objects such as tables, indexes, constraints, triggers, and more. This innovative architecture replaces the outdated MyISAM-based system tables, effectively making the handling of data dictionary information transactional and compliant with the ACID principles.

The …

The clone plugin was introduced in MySQL 8.0.17 and offers a convenient method for cloning data from either a local or remote MySQL server instance. This cloning process creates a physical snapshot of the data stored in InnoDB, including schemas, tables, tablespaces, and data dictionary metadata. The clone plugin allows for easy provisioning of MySQL servers by generating a fully functional data directory. In this blog post, we will explore the steps to configure a new MySQL replica using the clone plugin.

Installation of the Clone Plugin

To load the clone plugin during server startup, you can utilize the –plugin-load-add option and specify the library file containing the plugin. Ensure that you add this option each time the server starts when using this plugin-loading method. To make this configuration change, add the following lines to your my.cnf file, adjusting the plugin library file name extension according to your …

As businesses grow and develop, the requirements that they have for their data platform grow along with it. As such, one of the more common questions I get from my clients is whether or not their system will be able to endure an anticipated load increase. Or worse yet, sometimes I get questions about regaining normal operations after a traffic increase caused performance destabilization.

As the subject of this blog post suggests, this all comes down to proper capacity planning. Unfortunately, this topic is more of an art than a science, given that there is really no foolproof algorithm or approach that can tell you exactly where you might hit a bottleneck with server performance. But we can discuss common bottlenecks, how to assess them, and have a better understanding as to why proactive monitoring is so important when it comes to responding to traffic growth.

Hardware considerations

The first thing we have to consider …

In InnoDB, the undo log and the redo log are two indispensable components that play a vital role in maintaining data integrity and ensuring transactional consistency. Both logs are crucial in the ACID (Atomicity, Consistency, Isolation, Durability) properties of database systems. Additionally, they are essential for the Multi-Version Concurrency Control (MVCC) mechanism. In this blog post, we will delve into the differences between the InnoDB undo log and redo log, exploring their significance and providing code examples to illustrate their usage.

InnoDB Undo Log

The undo log, also known as the rollback segment, is a crucial part of the InnoDB storage engine. Its primary purpose is to support transactional consistency and provide the ability to …

This blog was originally published in July 2017 and was updated in August 2023.

It’s a pretty common question around here, so let’s see what we can do about that.

So, What is MySQL Partitioning?

Partitioning is a way in which a database (MySQL in this case) splits its actual data down into separate tables but still gets treated as a single table by the SQL layer.

When partitioning in MySQL, it’s a good idea to find a natural partition key. You want to ensure that table lookups go to the correct partition or group of partitions. This means that all SELECT, UPDATE, and DELETE should include that column in the WHERE clause. Otherwise, the storage engine does a scatter-gather and queries ALL partitions in a UNION that is not concurrent.

Generally, you must add the partition key into the primary key along …