Circus Oraclimus is back in town.  It was last time only four weeks ago and a few months before that as well, and while it the first few times was quite funny to watch the clowns, it  does not remain funny to see the same absurd tricks over and over again.

I am referring to this: http://bugs.mysql.com/bug.php?id=56889.

If you have both MySQL 5.5 and 5.6 installed on the same Windows system using the .msi installer you cannot upgrade 5.5.  The 5.5 installer refuses to run claiming that a ‘newer version’ [of 5.5.x] is installed.  It never was – and still is not – a problem upgrading 5.1. with 5.5 (and 5.6) installed.  So this is a bug and it is verified. And it was actually fixed by Vladislav Vaintrub before he left Oracle for Monty Program 1½ years ago.  For some reason the fix failed to be committed and never was included …

Installing Apache2 With PHP5 And MySQL Support On Ubuntu 12.04 LTS (LAMP)

LAMP is short for Linux, Apache, MySQL, PHP. This tutorial shows how you can install an Apache2 webserver on an Ubuntu 12.04 LTS server with PHP5 support (mod_php) and MySQL support.

In April, I got to give a talk at Percona Live, about why The Right Read Optimization is Actually Write Optimization. It was my first industry talk, so I was delighted when someone in the audience said “I feel like I just earned a college credit.”

Box offered to host everyone’s slides from the conference here (mine is here). A big thanks from me to Sheeri Cabral, for recording my talk and posting it online!

The focus of the talk …

When preparing for the the IOUG Collaborate 12 deep dive on deploying Oracle Databases for high Availability, I wanted to provide some feedback on what hardware components are failing most frequently and which ones are less frequently. I believe I have reasonably good idea about that but I thought that providing some more objective data would be better. I couldn’t find and results of a more scientific research so I decided to organize a poll. This blog post shows the results and I promised to share it with several groups.

The results are also in the presentation material but it might be hidden deep into 100+ slides so here is the dedicated blog with some comments on the …

Read the original article at Consulting essentials: Getting the business

Over the years, a lot of people have approached me asking how to become a tech consultant. What do I need to do to get started? How can I take my first step?

I also hear from managers and CEOs that have asked how I got my start, and how I keep the business running. What lessons from consulting can be applied to startups and small businesses? Having worked independently for many years I’ve built up my own cache of strategies and methods which I hope can be helpful to anyone looking to strike it out on their own.

This is the first of a series of three articles on consulting essentials. Part two covers …

The good news is that we have just released plenty of MariaDB & MySQL training dates covering the summer months and even into October across the globe.    This new training calendar includes all of our current training courses in plenty of locations both in North America and Europe. 

read more

It feels like every minute a PHP developer somewhere on this planet starts implementing something aching to a CMS from scratch. Some do it because their project is "so big" it that it "obviously needs" a custom solution. Some do it because their project is "so small" it "obviously needs" just a few days of hacking .. to build a custom solution. Let me briefly focus on the later group. Working in a company with less than 10 people building websites for customers a project needs a bit of a CMS to manage those 10 "semi static" pages seems to be the poster child example of this group. The devs whip up a DB table, slap an ORM in front, maybe even use some generator for the admin UI. Done. Later the clients also wants versioning and luckily many ORMs provide some solution for that. Easy. Permissions? Most frameworks provide some ACL system. Child pages? ORM has some tree algorithm supported. Fulltext search? Integrate ElasticSearch. Custom page types? Uhm …

MySQL 5.6 Replication - Global Transaction IDs

On Wednesday (16th May 2012), Mat Keep and I will be presenting the new replication features that are previewed as part of the latest MySQL 5.6 Development Release. If you’d like to attend then register here.

MySQL 5.6 delivers new replication capabilities which we will discuss in the webinar:

• High performance with Multi-Threaded Slaves and Optimized Row Based Replication
• High availability with Global Transaction Identifiers, Failover Utilities and Crash Safe Slaves & Binlog
• Data integrity with Replication Event Checksums
• Dev/Ops agility with new Replication Utilities, Time Delayed Replication and more

In class today, we reviewed pass-by-value (IN-only mode) parameters and pass-by-reference (INOUT and OUT mode) parameters for stored procedures. The analogy that finally seemed to hit home for the students was linking the modes to the story of Alice in Wonderland.

Here’s the analogy and below is the code to support it:

“A pass-by-value parameter in a procedure is like sending an immutable copy of Alice into the rabbit hole, which means she can’t shrink, grow, or learn throughout the story; whereas, a pass-by-reference parameter in a procedure is like sending Alice into the rabbit hole where she can shrink, grow, fight the Jabberwocky, and learn things that make her life better when she exits the …

Sysbench has three distribution for random numbers: uniform, special and gaussian. I mostly use uniform and special, and I feel that both do not fully reflect my needs when I run benchmarks. Uniform is stupidly simple: for a table with 1 mln rows, each row gets equal amount of hits. This barely reflects real system, it also does not allow effectively test caching solution, each row can be equally put into cache or removed. That’s why there is special distribution, which is better, but to other extreme – it is skewed to very small percentage of rows, which makes this distribution good to test cache, but it is hard to emulate high IO load.

That’s why I was looking for alternatives, and Zipfian distribution seems decent one. This distribution has a parameter θ (theta), which defines how skewed the distribution is. A physical sense of this parameter, if to apply …