Author: MySQL Planet

Feed: Planet MySQL; Author: MySQL Performance Blog; Although how range_optimizer_max_mem_size operates is explained in the official doc, it’s not a well-known variable and surely not a variable you need to modify under most circumstances. But from time to time we get some performance tickets related to this.What problem does this variable cause if it is not properly sized? Let’s find out with an example!Given the following table definition: CREATE TABLE `joinit` (   `i` int(11) NOT NULL AUTO_INCREMENT,   `s` varchar(64) DEFAULT NULL,   `t` time NOT NULL,   `g` int(11) NOT NULL,   PRIMARY KEY (`i`) ) ENGINE=InnoDB AUTO_INCREMENT=2490316 DEFAULT CHARSET=latin1CREATE TABLE `joinit` (  `i` ... Read More

Feed: Planet MySQL; Author: Tiago L. Alves; MySQL NDB Cluster is an open-source in-memory distributed database developed for high-availability (99.999% or more) and predictable query times. It can be found at the core of gaming, banking, telecommunication, and online services. Benchmarks [, ] have shown latencies in the order of 5–10 ms per transaction and throughput of 1.4M New Order TPM using a common 2-node configuration (each transaction consisting of 30 SQL statements — DBT2 benchmark).While the specific performance requirements of each customer might vary, from the product side it’s critical to ensure that performance is stable from version to ... Read More

Feed: Planet MySQL; Author: Severalnines; In a previous blog, we had discussed how to migrate a standalone Moodle setup to scalable setup based on a clustered database.  The next step you will need to think about is the failover mechanism - what do you do if and when your database service goes down.  A failed database server is not unusual if you have MySQL Replication as your backend Moodle database, and if it happens, you will need to find a way to recover your topology by for instance promoting a standby server to become a new primary server. Having automatic ... Read More

Feed: Planet MySQL; Author: Oracle MySQL Group; As a continue of the regular blog posts informing you about where you can find MySQL Community & MySQL team at, please find below a list of shows you can join and listen MySQL talks & sessions.  January 2021: Coud Native Meetup/VIRTUAL, January 26, 2021 - URL to be provided later on. Frederic Descamps, the MySQL User Group Manager will talk on: "MySQL 8.0: Why to use MySQL 8.0 and how to deploy a web application in OCI using MySQL Database Service"  Scheduled for January 26th as EMEA & JAPAC session & January 27th, 2021 ... Read More

Feed: Planet MySQL; Author: Bernd Ocklin; As of today a new version of MySQL NDB Cluster is available. First of all this release fixes various bugs, enhancing the stability and robustness of cluster further. Already in 8.0.21 MySQL the NDB team started to remove racially insensitive terminology from its configuration files, command line options, documentation and source code. In 8.0.23 we now hope to have finalized this work. Automated thread configuration is a new feature added. If enabled it will automatically run NDB with the ideal number of threads based on the number of physical cores and cpus of the ... Read More

Feed: Planet MySQL; Author: Severalnines; Data is an essential part of running a Moodle environment. Should the IT operations team lose data accidentally, then it could lead to a huge loss. So, to protect valuable information, sysadmins need to back up their Moodle database. Backups are one of the most important things to take care of while managing a database. In this blog we are going to look into how to backup your Moodle database using ClusterControl. ClusterControl provides you with centralized backup management for the Moodle databases, and it provides you with hot backups of large datasets, point in ... Read More

Feed: Planet MySQL; Author: MySQL Performance Blog; Large replication topologies are quite common nowadays, and this kind of architecture often requires a quick method to rebuild a replica from another server.The Clone Plugin, available since MySQL 8.0.17, is a great feature that allows cloning databases out of the box. It is easy to rebuild a replica or to add new nodes to a cluster using the plugin. Before the release of the plugin, the best open-source alternative was Percona XtraBackup for MySQL Databases.In this blog post, we compare both alternatives for cloning purposes. If you need to perform backups, Percona ... Read More

Feed: Planet MySQL; Author: Keith Hollman; https://www.syone.com/events/webinars-improving-security-compliance-mysql-enterprise-edition We have never had to be so careful and keep safe with respect to our health as ever before. I don’t have to go into details. For the health and safe-keeping of our IT infrastructure, we always remember our weaknesses when we suffer too. It’s probably human nature. So let’s be proactive where we can. IT Security has a lot to do with reducing the exposure of the system, controlling the risk and minimizing the attackers options. Assess, Prevent, Detect and Recover: MySQL Enterprise Security can help you fulfill all of your security ... Read More

Feed: Planet MySQL; Author: Severalnines; MyISAM is one of the most popular storage engines in MySQL. MyISAM frequently is the second choice after InnoDB - in this blog post we will try to find out how best to work with this engine. What is MyISAM? MyISAM is one of MySQL’s storage engines. MyISAM is based on ISAM (Indexed Sequential Access Method), an indexing algorithm developed by IBM that allows retrieving information from large sets of data in a fast way. However, it does not do very well when simultaneously reading from and writing to one table, due to its table ... Read More

Feed: Planet MySQL; Author: Daniel Nichter; This page is a reboot of the original written 15 years ago in 2005. Back then, I must have been using MySQL 4.1 or 5.0. Today, I am using MySQL 8.0.22. A lot changed in MySQL from 4.1 to 8.0, but it still has the same Select_% and Sort_% status variables which are equally important today in 2021. Let’s examine them in greater detail and with better examples. The MySQL Select_% and Sort_% status variables (metrics) are: Select_scan Select_range Select_full_join Select_full_range_join Select_range_check Sort_scan Sort_range Sort_merge_passes Sort_rows Using MySQL 8.0.22 Community, the test tables are: ... Read More