I’ve previously shared my excitement over the coming Oracle Certified Professional exams for MySQL 5.6 (both Developer and DBA), and I’m putting my (employer’s) money where my mouth is – I’ve registered to sit for the DBA exam in early November (some test sites have limited opportunities; interested candidates should consider booking now).  Here’s why I think others should do the same:

Low cost

During the beta period (through December 14), the cost of the exam is only $50 USD.  That’s barely more than the cost of a book or study guide these days, and a significant savings from the normal exam prices.

Full certification

Those who pass the exam will be given a full certification – not some lesser “beta certification.”  There’s no distinction between those who …

Quite some time ago, I published scripts to implement password policies for MySQL, and promised to show how to expose violations of that policy via MySQL Enterprise Monitor (MEM).  That stalled somewhat with other objectives, but I want to revisit it now that MEM 3.0 is GA.  If you haven’t tried MEM 3.0 yet, consider doing so – it’s quick and easy to set up.

Many people don’t realize that MEM can be extended to monitor things beyond MySQL Server health, including visibility into application state as observed from the database.  In part of the hands-on-lab I recently led at MySQL Connect, we …

This Wednesday in our next webinar I’ll share how to configure a better-performing MySQL 5.6 server. You’ll lean a practical approach to generating a sensible configuration file that sets what is needed and omits what is not.

Why dedicate an entire webinar to the new configuration settings within MySQL 5.6? Mainly because the default configuration files that come with MySQL 5.6 are not designed for high volume production use, and I’ve seen many MySQL incidents caused by poor configuration. Hopefully my advice will save you the headache of tweaking the variables within MySQL’s configuration files in order to work within your organization’s unique business environment.

And while I’ll be …

You may have already seen the news: Oracle is launching an updated certification for MySQL Developers, based on MySQL Server 5.6.  This is exciting to me for several reasons that I want to share:

Only one exam

Earlier versions of the MySQL Developer certification required sitting for two separate exams.  One goal in redefining the certification process was to make it more accessible to candidates, and reducing the cost – in both time and money – developers need to invest in examinations.  This obviously presented a challenge to cover the same material – actually more, when you consider MySQL 5.6 features – in fewer questions, but we feel we’ve done it.

Content from the experts

Content creation for this exam has drawn from many different volunteers from a wide range of MySQL teams including Training, …

Being able to configure slaves to be crash-safe is one of the major improvements of MySQL 5.6 with regards to replication. However we noticed confusion on how to enable this feature correctly, so let’s clarify how it should be done.

In short

1. Stop MySQL on slave
2. Add relay_log_info_repository = TABLE and relay_log_recovery = ON in my.cnf
3. Restart MySQL and relax

The gory details

To fully understand why you should change the above settings if you want crash-safe slaves, let’s first look at the reasons why replication can break when a slave crashes.

On a slave, replication involves 2 threads: the IO thread which copies the binary log of the master to a local copy called the relay log and the SQL thread which then executes the queries written in the relay log. The current position of each thread is stored in a file: master.info for the IO thread …

MySQL 5.6 has a great many new features, including, but certainly not limited to a number of performance improvements. However, besides the widely talked-about features such as InnoDB support for full text search, optimizer, performance schema improvements and …

Thanks to everyone who attended last week’s webinar, Running MySQL 5.6 on Amazon RDS.” If you weren’t able to attend, the recording and slides are available for viewing/download (or, if you were able to attend and just want to see it again). I’ve also answered the questions I didn’t have a chance to field during the event:

Q: Would you recommend Amazon RDS over manually setting up MySQL/Percona server on an EC2 instance?
A: This depends on many factors including your data set size, workload, uptime requirements, what the rest of your stack looks like, and many other factors.

Q: At Q&A time, can you go more into 5.6 InnoDB full text search vs the Amazon search offering? …

Recently i had to manage big database installation that was running out of disk space. The partition on which the mysql datadir was located only had a few gigabytes free. Resizing the partition was not possible without a long downtime so that was no option. The installation had only innodb-tables so using symlinks was also not possible.

Luckily they were using MySQL 5.6 and the server had another partition with more than enough disk space available so i decided to use that partition for the biggest tables.

First get the 15 biggest tables:

root@mysqlserver [(none)]> set global innodb_stats_on_metadata=0; select table_schema, table_name "Table Name",round(sum(data_length+index_length)/1024/1024/1024,4) "Size (GB)" from information_schema.tables group by table_schema,table_name ORDER BY round(sum(data_length+index_length)) DESC LIMIT 15;
 Query OK, 0 rows affected (0.00 sec)
 …

A tip for all those cloud users that like cloning database servers (as reported in my book Effective MySQL – Replication Techniques in Depth).

Starting with MySQL 5.6, MySQL instances have a UUID. Cloning servers to quickly create slaves will result in the following error message.

mysql> SHOW SLAVE STATUSG
...
  Last_IO_Error: Fatal error: The slave I/O thread stops because master and slave have equal MySQL server UUIDs; these UUIDs must be different for replication to work.
...

The solution is simple. Clear our the file based configuration file (located in the MySQL datadir) and restart the MySQL instance.

$ rm -f /mysql/data/auto.cnf
$ service mysql restart

One longstanding complaint I have heard for the past several years, and still hear today, is that Amazon’s Relational Database Service (RDS) does not allow the configuration flexibility as running MySQL in an ec2 instance. While true, this ignores the consistent work that Amazon has done to provide access to the most important configuration variables needed to tune a MySQL instance (after all, how relevant is it for a customer to set bind_address in an RDS instance).

Let’s take a look visually:

MySQL provides 523 options (35 of them NDB specific, so aren’t relevant to RDS), while RDS provides (via the web UI) …