November 26, 2014

MariaDB: Selective binary logs events

In the first post in a series on MariaDB features we find interesting, we begin with selectively skipping replication of binlog events. This feature is available on MariaDB 5.5 and 10. By default when using MySQL’s standard replication, all events are logged in the binary log and those binary log events are replicated to all slaves […]

Percona Live MySQL Conference and Expo 2013 – News from the Committee – Tutorial Selection Complete

As Percona Live London is raging in the UK, I thought it fitting to remind everyone about the next big Percona Live: MySQL Conference and Expo 2013 in Santa Clara, Californa on April 22-25, 2013.  You can register NOW for this conference, and the Super Saving Registration deadline ends on December 28th, so be sure to […]

When the subselect runs faster

A few weeks ago, we had a query optimization request from one of our customer. The query was very simple like:

This column in the table is looks like this:

The table have 549252 rows and of course, there is an index on the col1. MySQL estimated the cardinality of that index as […]

Introducing tpce-like workload for MySQL

We have been using tpcc-mysql benchmark for long time, and there many results published in our blog, but that’s just single workload. That’s why we are looking into different benchmarks, and one of them is TPCE. Yasufumi made some efforts to make TPCE working with MySQL, and we are making it available for public consideration. […]

Faster MySQL failover with SELECT mirroring

One of my favorite MySQL configurations for high availability is master-master replication, which is just like normal master-slave replication except that you can fail over in both directions. Aside from MySQL Cluster, which is more special-purpose, this is probably the best general-purpose way to get fast failover and a bunch of other benefits (non-blocking ALTER […]

What would you like to hear about on MySQL Users Conference 2008 ?

It is submission time now, with about one week left till proposal submission deadline. Both me and Vadim had submitted few talks to the Grand Jury which will make elite selection of sessions for MySQL Users Conference and we plan to submit few more. Our experience in MySQL is rather broad – we can prepare […]

SELECT LOCK IN SHARE MODE and FOR UPDATE

Baron wrote nice article comparing locking hints in MySQL and SQL Server. In MySQL/Innodb LOCK IN SHARE MODE and SELECT FOR UPDATE are more than hints. Behavior will be different from normal SELECT statements. Here is simple example:

Sys Schema for MySQL 5.6 and MySQL 5.7

Performance Schema (P_S) has been available since MySQL 5.5, more than 4 years ago. It is still difficult to see production servers with P_S enabled, even with MySQL 5.6 where the feature is enabled by default. There have been several complaints like the overhead, that the fix is a work in progress, and the ease […]

How a set of queries can be killed in MySQL using Percona Toolkit’s pt-kill

You might have encountered situations where you had to kill some specific select queries that were running for long periods and choking the database. This post will go into more detail with an example of report query offloading. Report query (select) offloading to a slave server is a common practice to reduce the workload of the […]

RDS for Aurora unveiled at AWS re:Invent

One of the big announcements at the Amazon Web Services re:Invent 2014 conference this week was the unveiling of Aurora. The result of years of internal work, Aurora, currently in preview, is a MySQL 5.6-compatible option that “combines the speed and availability of high-end commercial databases with the simplicity and cost-effectiveness of open source databases” on […]