October 1, 2014

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 […]

Using delayed JOIN to optimize count(*) and LIMIT queries

In many Search/Browse applications you would see main (fact) table which contains search fields and dimension tables which contain more information about facts and which need to be joined to get query result. If you’re executing count(*) queries for such result sets MySQL will perform the join even if you use LEFT JOIN so it […]

When (and how) to move an InnoDB table outside the shared tablespace

In my last post, “A closer look at the MySQL ibdata1 disk space issue and big tables,” I looked at the growing ibdata1 problem under the perspective of having big tables residing inside the so-called shared tablespace. In the particular case that motivated that post, we had a customer running out of disk space in his […]

Q&A: Even More Deadly Mistakes of MySQL Development

On Wednesday I gave a presentation on “How to Avoid Even More Common (but Deadly) MySQL Development Mistakes” for Percona MySQL Webinars.  If you missed it, you can still register to view the recording and my slides. Thanks to everyone who attended, and especially to folks who asked the great questions.  I answered as many as we had […]

Managing shards of MySQL databases with MySQL Fabric

This is the fourth post in our MySQL Fabric series. In case you’re joining us now, we started with an introductory post, and then discussed High Availability (HA) using MySQL Fabric here (Part 1) and here (Part 2). Today we will talk about how MySQL Fabric can help you scale out MySQL databases with sharding. Introduction At the […]

How to identify and cure MySQL replication slave lag

Here on the Percona MySQL Support team, we often see issues where a customer is complaining about replication delays – and many times the problem ends up being tied to MySQL replication slave lag. This of course is nothing new for MySQL users and we’ve had a few posts here on the MySQL Performance Blog […]

A conversation with 5 Facebook MySQL gurus

Facebook, the undisputed king of online social networks, has 1.23 billion monthly active users collectively contributing to an ocean of data-intensive tasks – making the company one of the world’s top MySQL users. A small army of Facebook MySQL experts will be converging on Santa Clara, Calif. next week where several of them are leading […]

Calvin Sun on MySQL at Twitter, Percona Live 2014 and Facebook

Twitter’s Calvin Sun (@Calvinsun2012) is looking forward to the fast-approaching Percona Live MySQL Conference and Expo this April 1-4 in Santa Clara, Calif. He’ll be speaking, yes, but he’s also looking forward to learning from his peers – particularly those at Facebook. Both companies, he explained, are in the rather unique positions of unprecedented rapid […]

Percona Toolkit collection: pt-visual-explain

This is the first in a series of posts highlighting a few of the seldom-used but still handy Percona Toolkit tools. Have you ever had a problem understanding the EXPLAIN statement output? And are you the type of person who would rather use the command line than a GUI application? Then I would recommend that […]

Schema Design in MongoDB vs Schema Design in MySQL

For people used to relational databases, using NoSQL solutions such as MongoDB brings interesting challenges. One of them is schema design: while in the relational world, normalization is a good way to start, how should we design our collections when creating a new MongoDB application? Let’s see with a simple example how we would create […]