August 22, 2014

Row-based replication, MySQL 5.6 upgrades and temporal data types

Whither your rollback plan? MySQL 5.6 upgrades are in full swing these days and knowing how to safely upgrade from MySQL 5.5 to 5.6 is important. When upgrading a replication environment, it’s important that you can build a migration plan that safely allows for your upgrade with minimal risk — rollback is often a very […]

Using Apache Hadoop and Impala together with MySQL for data analysis

Apache Hadoop is commonly used for data analysis. It is fast for data loads and scalable. In a previous post I showed how to integrate MySQL with Hadoop. In this post I will show how to export a table from  MySQL to Hadoop, load the data to Cloudera Impala (columnar format) and run a reporting […]

Database security: Why should you review yours?

Ah database security… the black sheep of topics and something you would really rather not have to deal with right? I mean surely all the fanfare and paranoia is reserved for the neck beards with tinfoil hats whom live in their own D.I.Y Faraday cage … that must be it … it just has to […]

Using Percona rsync repositories to set up the local CentOS mirror

One of the more popular support requests we get involves setting up the official Percona rsync repositories that can be used to set up local mirrors. I’m glad to announce that this was implemented recently. You can now access the rsync repository at: rsync:// Setting up the local mirror can be useful if you have […]

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 […]

10 MySQL settings to tune after installation

When we are hired for a MySQL performance audit, we are expected to review the MySQL configuration and to suggest improvements. Many people are surprised because in most cases, we only suggest to change a few settings even though hundreds of options are available. The goal of this post is to give you a list […]

Renaming database schema in MySQL

One of the routine tasks for a DBA is renaming database schemas, and as such MySQL added a command to carry out that purpose called “RENAME DATABASE <database_name>”. However this command just made it through a few minor releases before being discontinued (from MySQL 5.1.7 to 5.1.23). Here’s a link to the reference manual regarding […]

Multi-Data Center MySQL with Continuent Tungsten: Dec. 11 webinar

I’m looking forward to next week’s MySQL webinar with Robert Hodges, CEO of Continuent. We’ll be speaking on the topic “Multi-Data Center MySQL with Continuent Tungsten.” You’re not alone if you’ve been vexed when trying to assemble multi-master, multi-site MySQL clusters. Whether that was a move from a single database server to a scalable cluster, […]

utf8 data on latin1 tables: converting to utf8 without downtime or double encoding

Here’s a problem some or most of us have encountered. You have a latin1 table defined like below, and your application is storing utf8 data to the column on a latin1 connection. Obviously, double encoding occurs. Now your development team decided to use utf8 everywhere, but during the process you can only have as little […]