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How to create a rock-solid MySQL database backup & recovery strategy

Have you ever wondered what could happen if your MySQL database goes down? Although it’s evident such a crash will cause downtime – and surely some business impact in terms of revenue – can you …


How to obtain the MySQL version from an FRM file

I recently helped a customer figure out why a minor version MySQL upgrade was indicating that some tables needed to be rebuilt. The mysql_upgrade program should be run for every upgrade, no matter how big …


MySQL QA Episode 4: QA Framework Setup Time!

Welcome to MySQL QA Episode 4! In this episode we’ll look into setting up our QA Framework: percona-qa, pquery, reducer & more. 1. All about percona-qa 2. pquery

3. reducer.sh

4. Short introduction to …


MySQL QA Episode 3: How to use the debugging tool GDB

Welcome to MySQL QA Episode 3: “Debugging: GDB, Backtraces, Frames and Library Dependencies” In this episode you’ll learn how to use debugging tool GDB. The following debugging topics are covered: 1. GDB Introduction 2. Backtrace, Stack …


Using Cgroups to Limit MySQL and MongoDB memory usage

Quite often, especially for benchmarks, I am trying to limit available memory for a database server (usually for MySQL, but recently for MongoDB also). This is usually needed to test database performance in scenarios with …


Practical MySQL Performance Optimization (July 2 webinar)

Applications often become impacted by MySQL performance. Optimization is the obvious solution but where to start? Join me on July 2 at 11 a.m. Pacific and I’ll show you how to optimize MySQL in a …


Oracle license revenue and the MySQL ecosystem

Oracle was in the news recently with the story of its license revenue declining as much as 17% in the recent quarter. This is blamed on transitioning to the cloud in some publications, but others, …


Q&A: High availability when using MySQL in the cloud

Last week I hosted a webinar on using MySQL in the cloud for High Availability (HA) alongside 451 Research analyst Jason Stamper. You can watch the recording and also download the slides (free) here. Just …


Getting EXPLAIN information from already running queries in MySQL 5.7

When a new version of MySQL is about to be released we read a lot of blog posts about the performance and scalability improvements. That’s good but sometimes we miss some small features that can …


Speed up GROUP BY queries with subselects in MySQL

We usually try to avoid subselects because sometimes they force the use of a temporary table and limits the use of indexes. But, when is good to use a subselect? This example was tested over …