Using Explain to Improve SQL Query Performance
When it comes to the query tuning, EXPLAIN is one the most important tool in the DBA’s arsenal. Why is a given query slow, what does the execution plan look like, how will JOINs be...
Webinar Replay: Replication Topology Changes for MySQL
Thanks to everyone who joined us for our recent live webinar on ‘Replication Topology Changes for MySQL and MariaDB’ led by Krzysztof Książek, Senior Support Engineer at Severalnines. The replay and slides to the webinar...
An Overview of MySQL Database Indexing
An index is a data structure that sorts a number of records on one or more fields, and speeds up data retrieval. This is to avoid scanning through the disk blocks that a table spans,...
High Availability MySQL on cPanel with Galera Cluster
cPanel is a very popular Linux hosting control panel, used not only by hosting providers but also enterprise and goverment bodies. For large scale hosting environments hosting mission critical databases, how do you integrate cPanel...
Webinar Replay: Schema Changes for MySQL Replication & Galera Cluster
Thanks to everyone who joined us for our recent live webinar on ‘Schema Changes for MySQL Replication & Galera Cluster’ led by Krzysztof Książek, Senior Support Engineer at Severalnines. The replay and slides to the...
Analyzing Your SQL Workload Using pt-query-digest
In our previous post, we discussed the different ways to collect data about slow queries - MySQL offers slow log, general log and binary log. Using tcpdump, you can grab network traffic data - a...
How to Perform an Online Upgrade of Galera Cluster to MySQL 5.6
Oracle released a GA version of MySQL 5.6 in February 2013, Codership released the first GA in their patched 5.6 series in November 2013. Galera Cluster for MySQL 5.6 has been around for almost 2...
Understanding the MySQL Query Tuning Process
Query tuning is something that a DBA does on a daily basis - analyse queries and updates, how these interact with the data and schema, and optimize for performance. This is an extremely important task...
MySQL Configuration: Tuning for Performance
A database server needs CPU, memory, disk and network in order to function. Understanding these resources is important for a DBA, as any resource that is weak or overloaded can become a limiting factor and...
Architecting for Failure – Disaster Recovery of MySQL Galera Cluster
Failure is a fact of life, and cannot be avoided. No IT vendor in their right mind will claim 100% system availability, although some might claim several nines :-) We might have armies of ops...
Webinar Replay: Designing for High Availability for MySQL
Thanks to everyone who joined us yesterday for this live session on designing HA for MySQL led by Krzysztof Książek, Senior Support Engineer at Severalnines. The replay and slides to the webinar are now available...
An Overview of MySQL Database Upgrades
Database vendors typically release patches with bug/security fixes on a monthly basis, why should we care? The news is full of reports of security breaches and hacked systems, so unless security is not a concern,...