Fragmentation is a common concern in some database systems. Highly fragmented tables can affect performance and resource allocation. But reducing fragmentation often involves rebuilding the table completely. This blog post will discuss fragmentation and its impact on InnoDB.

What is fragmentation?

We say that something is fragmented when it is formed by parts that are separate or placed in a different order than the natural one. In databases, we can experiment with different types of fragmentation:

• Segment Fragmentation: segments are fragmented; they are stored not following the order of data, or there are empty pages gaps between the data pages.
• Tablespace Fragmentation: the tablespace is stored in non-consecutive filesystem blocks.
• Table Fragmentation: data is stored not following the primary key order (heap tables), …

Learn how Multi-Valued Indexing in MySQL 8.0 can enhance query performance by efficiently indexing and querying JSON arrays. Discover the benefits, implementation steps, and considerations for optimizing your MySQL database.

1. Multi-Valued Indexing in MySQL 8.0
2. Understanding Multi-Valued Indexes and their benefits
3. Creating Multi-Valued Indexes in MySQL …

Learn how to seamlessly add a new node to MySQL Group Replication from a backup. Scale your cluster, save time, and efficiently manage data updates and recoveries.

1. Hot Physical backup approach
2. Clone plugin approach
3. Logical backup approach

We highly recommend checking out our previous blog post on …

This blog post was originally published in November 2017 and was updated in June 2023.

In this blog, we’ll provide a comparison between MariaDB vs. MySQL (including Percona Server for MySQL).

Introduction: MariaDB vs. MySQL

The goal of this blog post is to evaluate, at a higher level, MariaDB vs. MySQL vs. Percona Server for MySQL side-by-side to better inform the decision making process. It is largely an unofficial response to published comments from the MariaDB Corporation.

It is worth noting that Percona Server for MySQL is a drop-in compatible branch of MySQL, where Percona contributes as much as possible upstream. MariaDB Server, on the other hand, is a fork of MySQL 5.5. They cherry-picked MySQL features and don’t …

Learn how the parallel index rebuild feature in MySQL 8.0.31 improves performance by optimizing index and column additions. Explore the multithreaded insert phase, sort index build process, and system configurations for enhanced efficiency.

1. Understanding Sorted Index Build
   1. When does InnoDB use a sort index build approach?
2. Phases of Sort …

Discover how to troubleshoot a MySQL replica IO thread stuck in a connecting state. Learn about the replication architecture, security group rules for AWS EC2 instances, and how to address common issues like network restrictions and bind address configuration.

MySQL is a powerful database management and a widely used cloud database service. One of its key features is the ability to create replicas of a master database to improve its availability and scalability. However, at times the IO thread in a MySQL replica may get stuck in a connecting state, which can cause replication issues and affect the overall data consistency …

Table of contents:

1. Introduction
2. Common reasons for switching the primary node
3. Primary Promotion and its importance
4. Methods for switching the primary node
5. …

In this blog, I will share the steps I took to debug an error ‘ERROR 1030 (HY000): Got error 168 – ‘Unknown (generic) error from engine’ from storage engine’ while…

The post How to fix 1030 Unknown generic error from engine in MySQL first appeared on Change Is Inevitable.

MySQL uses Redo Logs internally during crash recovery to correct data written by incomplete transactions. But how do you know what the right Redo Log size is? We will walk through how to figure that out in this blog.

We already have a couple of posts related to this topic. “How to calculate a good InnoDB log file size” and “How to Choose the MySQL innodb_log_file_size.” The first one has the formula I’ll mention in this blog, and the second has more details regarding Redo Logs. Most of it is still valid, just replace innodb_log_file_size / innodb_log_files_in_group with innodb_redo_log_capacity.

So in this one, I want to focus on two things:

1. Present the new way of working with Redo Logs (No …

ProxySQL is an open-source MySQL proxy server, meaning it serves as an intermediary between a MySQL server and the applications that access its databases. ProxySQL can improve performance by distributing traffic among a pool of multiple database servers.

Consider 2 slaves are routed under Proxysql , In any one of the slave, if the replication is broken, we could still see the traffic routing to the broken replication slave. We can make Proxy to not send traffic to broken replication slave, by setting appropriate value to the variable mysql-monitor_slave_lag_when_null

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