April 19, 2014

Generating test data for MySQL tables

One of the common tasks requested by our support customers is to optimize slow queries. We normally ask for the table structure(s), the problematic query and sample data to be able to reproduce the problem and resolve it by modifying the query, table structure, or global/session variables. Sometimes, we are given access to the server […]

Getting Percona PAM to work with Percona Server & its client apps

Percona Server is bundled with the PAM plugin which opens a plethora of ways to authenticate to MySQL such as restricting time when users can connect to MySQL, authenticate via a USB key, authenticate to an external authentication system such as LDAP and many, many more PAM compatible mechanisms. If you want to use PAM […]

How to recover table structure from InnoDB dictionary

To recover a dropped or corrupt table with Percona Data Recovery Tool for InnoDB you need two things: media with records(ibdata1, *.ibd, disk image, etc.) and a table structure. Indeed, there is no information about the table structure in an InnoDB page. Normally we either recover the structure from .frm files or take it from […]

Analyzing Slow Query Table in MySQL 5.6

Next week I’m teaching an online Percona Training class, called Analyzing SQL Queries with Percona Toolkit.  This is a guided tour of best practices for pt-query-digest, the best tool for evaluating where your database response time is being spent. This month we saw the GA release of MySQL 5.6, and I wanted to check if any […]

How to recover deleted rows from an InnoDB Tablespace

In my previous post I explained how it could be possible to recover, on some specific cases, a single table from a full backup in order to save time and make the recovery process more straightforward. Now the scenario is worse because we don’t have a backup or the backup restore process doesn’t work. How […]

Recovering CREATE TABLE statement from .frm file

So lets say you have .frm file for the table and you need to recover CREATE TABLE statement for this table. In particular when we do Innodb Recovery we often get .frm files and some mess in the Innodb tablespace from which we have to get data from. Of course we could relay on old […]

How to find bugs in MySQL

Finding bugs in MySQL is not only fun, it’s also something I have been doing the last four years of my life. Whether you want to become the next Shane Bester (who is generally considered the most skilled MySQL bug hunter worldwide), or just want to prove you can outsmart some of the world’s best […]

How to log slow queries on Slave in MySQL 5.0 with pt-query-digest

Working as a Percona Support Engineer, every day we are seeing lots of issues related to MySQL replication. One very common issue is slave lagging. There are many reasons for slave lag but one common reason is that queries are taking more time on slave then master. How to check and log those long-running queries?  From […]

Engineer duo from Google, LinkedIn join again for InnoDB talks

Google senior systems engineer Jeremy Cole is once again teaming with LinkedIn senior software engineer Davi Arnaut for two InnoDB-focused sessions at the upcoming Percona Live MySQL Conference and Expo 2014 this April 1-4 in Santa Clara, California. The duo will present “InnoDB: A journey to the core II” on April 2 and “InnoDB: A […]

Percona Cloud Tools: Making MySQL performance easy

One of our primary focuses at Percona is performance. Let me make some statements on what is “performance.” In doing so I will refer to two pieces of content: Carry Millsap’s talk “Performance Instrumentation: Beyond What You Do Now” [1] White Paper (by Peter and Baron) “Goal-Driven Performance Optimization” [2] I highly recommend that you […]