On MySQL and Percona Server for MySQL, there is a schema called information_schema (I_S) which provides information about database tables, views, indexes, and more.

A lot of useful information can be retrieved from this schema, for example, table metadata and foreign key relations, but trying to query I_S can induce performance degradation if your server is under heavy load, as shown in the following example test.

Disclaimer: This blog post is meant to show a less-known problem but is not meant to be a serious benchmark. The percentage in degradation will vary depending on many factors {hardware, workload, number of tables, configuration, etc.}.

Test

The test compares a baseline of how the server behaves while “under heavy load but no queries against I_S” vs. ” under heavy load + I_S queries” to …

I changed the format a little bit for this week’s OpenLampTech newsletter. Still sharing the same great content, but, with less rambling on my part. Let me know what you think and thank you for reading.

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 #71, I’m sharing great content on:

• Finding duplicate rows with SQL
• User input in Laravel securely
• WordPress Loop and Query Loop compared
• Get the current date in PHP
• And a whole lot more.

I appreciate you reading …

MySQL Books is a series of articles that puts the spotlight on books dedicated to MySQL that deserve a place in the library of any MySQL DBA or developer.

Note: The content was originally published at PlanetScale Connection pooling is a commonly used technique in modern applications to manage database connections efficiently. It involves creating a cache of database connections that the application can use as needed. Instead of creating a new connection for each request to the database, the application retrieves a connection from the pool. After the application finishes using the connection, it is returned to the pool to be reused later, rather than being closed outright.

Introducing new MySQL HeatWave features for lower cost and better performance

Time series forecasting is a technique for predicting future values of key metrics based on past events. It involves using time ordered events from past as well as other variables to predict future values. Multivariate time series forecasting can predict multiple time ordered variables, where each variable is dependent on its past value as well […]

MySQL HeatWave on AWS - New and upcoming capabilities in March and April 2023

Machine learning in MySQL HeartWave (aka HeatWave AutoML) offers a fully automated forecasting pipeline that can automatically preprocess, select the best algorithm, and tune its hyperparameters for a given time-series dataset resulting is unmatched model training performance and high forecasting accuracy. There is no additional cost for using machine learning in MySQL HeatWave.

In MySQL Server 8.0.32, Oracle fixed Bug #105761:

“mysqldump make a non-consistent backup with ‐‐single-transaction option” (this commit)

which caused a wave of complaints from users who could no longer do backups with the mysqldump utility because of the lack of the required privileges.

• Bug #109701 “Fix for #33630199 in 8.0.32 introduces regression when ‐‐set-gtid-purged=OFF”
• Bug #109685 “mysqldump has incompatible change in MySQL 8.0.32″

…

You might want to use binlog compression with MySQL/Percona Server for MySQL, but it can come with drawbacks. This article discusses the need for using binlog compression and the potential issues it may cause.

Binlog compression is a technique used to reduce the size of binary log files, which can become quite large over time. This can be especially important in situations where disk space is limited. However, it’s important to be aware that using binlog compression can also cause issues with replication.

Consider the following scenario: you have restored a backup that was taken from a replica node using Percona XtraBackup. Once the restoration is complete, you want to set up replication using the information from the xtrabackup_slave_info …