October 30, 2014

MySQL 5.6.10 Optimizer Limitations: Index Condition Pushdown

While preparing the webinar I will deliver this Friday, I ran into a quite interesting (although not very impacting) optimizer issue: a “SELECT *” taking half the time to execute than the same “SELECT one_indexed_column” query in MySQL 5.6.10. This turned into a really nice exercise for checking the performance and inner workings of one […]

Percona MySQL University, Raleigh just got better with AfterParty

We got a great response to our Percona MySQL University event in Raleigh With about a week to go before event we’re around 90% full, so if you plan to attend do not delay your registration until last minute. Also if you have registered before but can’t attend at this point please release your ticket […]

New Keynote Speakers and Sponsors and Applications Open for DotOrg Pavilion for Percona Live MySQL Conference and Expo

I’m pleased to announce the first of the Percona Live MySQL Conference and Expo 2013 keynote speakers and new sponsors including Amazon Web Services, Google, Clustrix, Scalebase, PalominoDB, Database Trends & Applications, and Linux Journal. We are also now accepting applications for the DotOrg Pavilion. Also, nominations are now being accepted for the 2013 MySQL […]

FOSDEM 2013: MySQL And Friends Community Dinner

Just like previous years, the ‘MySQL And Friends’ community is gathering to have a dinner on the Saturdaynight of FOSDEM. This time it is on February 2nd, 2013. This year, it will not be an Italian restaurant, but more a Belgian style restaurant, about 10 minutes walk from the FOSDEM event. Mirabelle: http://www.mirabelle.be/index.php?lang=en Chaussée de Boondael, […]

Be productive with the MySQL command line

Even if you are using a GUI tool to connect to your MySQL servers, one day or another, you will have to deal with the command line. So it is nice to know a few tips that can really make your work easier. Note: The commands below are only available for Unix/Linux. Using pager Most […]

A case for MariaDB’s Hash Joins

MariaDB 5.3/5.5 has introduced a new join type “Hash Joins” which is an implementation of a Classic Block-based Hash Join Algorithm. In this post we will see what the Hash Join is, how it works and for what types of queries would it be the right choice. I will show the results of executing benchmarks […]

Eventual Consistency in MySQL

We’re told that foreign key constraints are the best way to enforce logical referential integrity (RI) in SQL, preventing rows from becoming orphaned.  But then we learn that the enforcement of foreign keys incurs a significant performance overhead.1,2 MySQL allows us to set FOREIGN_KEY_CHECKS=0 to disable enforcement of RI when the overhead is too high.  But […]

Side load may massively impact your MySQL Performance

When we’re looking at benchmarks we typically run some stable workload and we run it in isolation – nothing else is happening on the system. This is not however how things happen in real world when we have significant variance in the load and many things can be happening concurrently. It is very typical to […]

MySQL data via a NoSQL solution, Free ticket to Percona Live London

The much-anticipated ability to access MySQL data via a NoSQL solution has been realized. Using HandlerSocket, significant performance gains can be realized for certain workloads. Sound like something you are interested in? Join us for Percona Live London to hear Ryan Lowe, Percona’s Director of American Consulting speak on this subject. In Ryan’s session he […]

How to debug long-running transactions in MySQL

Among the many things that can cause a “server stall” is a long-running transaction. If a transaction remains open for a very long time without committing, and has modified data, then other transactions could block and fail with a lock wait timeout. The problem is, it can be very difficult to find the offending code […]