So far most of the benchmarks posted about MySQL 5.6 use the sysbench OLTP workload. I wanted to test a set of queries which, unlike sysbench, utilize joins. I also wanted an easily reproducible set of data which is more rich than the simple sysbench table. The Star Schema Benchmark (SSB) seems ideal for this. [...]
Merit of Private Training
Percona has offered Training for years, and I have personally delivered my share of Public and Private training. Below are my thoughts on the different training delivery options and how to choose the one that fits your needs. The Onsite Public training is perhaps the most conventional type. We get people from different people and go over our standard [...]
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 [...]
Joining many tables in MySQL – optimizer_search_depth
Working on customer case today I ran into interesting problem – query joining about 20 tables (thank you ORM by joining all tables connected with foreign keys just in case) which would take 5 seconds even though in the read less than 1000 rows and doing it completely in memory. The plan optimizer picked was [...]
Percona XtraDB Cluster Feature 1: High Availability
There and in coming posts I am going to cover main features of Percona XtraDB Cluster. The first feature is High Availability. But before jumping to HA, let’s review general architecture of the Percona XtraDB Cluster.
Avoiding auto-increment holes on InnoDB with INSERT IGNORE
Are you using InnoDB tables on MySQL version 5.1.22 or newer? If so, you probably have gaps in your auto-increment columns. A simple INSERT IGNORE query creates gaps for every ignored insert, but this is undocumented behaviour. This documentation bug is already submitted. Firstly, we will start with a simple question. Why do we have [...]
Shard-Query turbo charges Infobright community edition (ICE)
Shard-Query is an open source tool kit which helps improve the performance of queries against a MySQL database by distributing the work over multiple machines and/or multiple cores. This is similar to the divide and conquer approach that Hive takes in combination with Hadoop. Shard-Query applies a clever approach to parallelism which allows it to [...]
Joining on range? Wrong!
The problem I am going to describe is likely to be around since the very beginning of MySQL, however unless you carefully analyse and profile your queries, it might easily go unnoticed. I used it as one of the examples in our talk given at phpDay.it conference last week to demonstrate some pitfalls one may [...]
The Doom of Multiple Storage Engines
One of the big “Selling Points” of MySQL is support for Multiple Storage engines, and from the glance view it is indeed great to provide users with same top level SQL interface allowing them to store their data many different way. As nice as it sounds the in theory this benefit comes at very significant [...]
Percona welcomes Ewen Fortune and Piotr Biel
Although we haven’t announced any new members in a while, the Percona team has continued to grow steadily behind the scenes. Our hiring policy is to have a few months’ provisional period to ensure the…, of course. Ewen has been a consultant and contractor before joining Percona, and has many years of experience in Oracle, MySQL, Unix systems ….
Piotr Biel lives in Poland, quite close to our other Polish team member (Maciek Dobrzanski). In his past as a system architect he … can do!
Ewen and Piotr, a very warm welcome to the Percona team from all of us, and we are so glad to …

