July 29, 2014

Recovering from a bad UPDATE statement

Did you just run an UPDATE against your 10 million row users table without a WHERE clause?  Did you know that in MySQL 5.5 that sometimes you can recover from a bad UPDATE statement?  This is possible if you are running in binlog_format=ROW ! Imagine this scenario:

We run an accidental UPDATE statement that […]

Percona’s Commitments to MySQL Users

You probably saw the Twitter storm over Oracle’s pricing changes and InnoDB in the last few days. The fear about Oracle removing InnoDB from the free version of MySQL was baseless — it was just a misunderstanding. Still, in the years since MySQL has been acquired by Sun, and then by Oracle, many MySQL users […]

Can MySQL temporary tables be made safe for statement-based replication?

A while ago I wrote about how to make MySQL replication reliable, part of which is to eliminate temporary tables. The idea is this: if a slave is stopped (or crashed) while a temporary table is open and is then restarted, the temporary table doesn’t exist anymore, and the slave will have problems trying to […]

State of MySQL Market and will Replication live ?

There are interesting posts these day about future of MySQL Replication by Brian Frank and Arjen. I think it very interesting to take a look at a bit bigger picture using framework from Innovators Dilemma and Innovators Solution. I’m not going to speak about disruption and commoditisation of Database Market, leaving this for Market talks, […]

What I learned while migrating a customer MySQL installation to Amazon RDS

Hi, I recently had the experience of assisting with a migration of a customer MySQL installation to Amazon RDS (Relational Database Service). Amazon RDS is a great platform for hosting your MySQL installation and offers the following list of pros and cons: You can scale your CPU, IOPS, and storage space separately by using Amazon […]

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 […]

Do not trust vmstat IOwait numbers

I’ve been running a benchmark today on my old test box with conventional hard drives (no raid with BBU) and noticed something unusual in the CPU utilization statistics being reported. The benchmark was run like this:

Which means: create 64 threads and hammer the database with queries as quickly as possible. As the test […]

High Availability with MySQL Fabric: Part II

This is the third post in our MySQL Fabric series. If you missed the previous two, we started with an overall introduction, and then a discussion of MySQL Fabric’s high-availability (HA) features. MySQL Fabric was RC when we started this series, but it went GA recently. You can read the press release here, and see this blog post from Oracle’s Mats […]

Installing Percona XtraDB Cluster 5.6 with the Docker open-source engine

In my previous post, I blogged about using Percona Server with Docker and have shown you how fast and easy it was to create a virtual environment with just a few commands. This time I will be showing you how to setup a three-node Percona XtraDB Cluster (PXC) 5.6 on the Docker open-source engine. Just […]

Errant transactions: Major hurdle for GTID-based failover in MySQL 5.6

I have previously written about the new replication protocol that comes with GTIDs in MySQL 5.6. Because of this new replication protocol, you can inadvertently create errant transactions that may turn any failover to a nightmare. Let’s see the problems and the potential solutions. In short Errant transactions may cause all kinds of data corruption/replication […]