One day, after taking a job using MySQL, I was writing a query quietly at my desk. It was around quittin’ time, and I was whipping up a new report on the monthly sales figures that the CEO needed for his board meeting in the morning. I, in my ignorance, wrote a nice query with a simple little sum() function. What I did not realize is this caused all my rows to sum up to one row when it really should’ve show several rows. This made my report completely inaccurate. Blindly trusting me as I had blindly trusted MySQL, the CEO presented my report to the board who decided that the company was grossly unprofitable and voted to shut it down. Only when I was waiting in the bread line at my local workhouse did I realize my mistake.

That’s me in the bowler.

Okay, so that’s totally made up. Mostly. I caught the error …

Measuring how well a MySQL is doing can be tough – most metrics are simply proxies for actual performance. Thankfully, the Percona build of MySQL allows you to see exactly how long your queries are taking. It provides a diagnostic view that shows how long queries take, allowing you to gauge its real-world performance. I’ll get to that in a little bit. Before we do that, I want to talk about some other tools you can use.

You can dump the status of the system by running “show global status;”. This will give you how many connections have aborted, rows written, and how long the server has been up. This is historical info that’s erased when you flush it or when the server restarts (planned or unplanned). By sampling at regular intervals, you can also build monitoring scripts that measure changes over time …

When you setup a monitoring system for SQL Server, you often use thresholds to determine when an instance is healthy. You might say that you want to be alerted when CPU use is over 90% or when there’s only 10% of disk space left. The trouble with these thresholds is that they will often throw off false positives, or send you an alert when really nothing is wrong. Simple thresholds often have to be tuned to the individual instance, since a server with 10 TB still has 1 TB of space left at 90% disk use.

Baron Schwartz blogged about this issue in an article and he’s been creating software that monitors MySQL beyond simple thresholds, after stating that they do not work in most cases. He makes a good …

I am doing a reporting proof-of-concept (POC) for my company. Business intelligence (BI) is often the last thing that gets thought of during an application’s life cycle because it’s only really necessary after you get customers. Before that, the main focus is on application features. Soon after launch, your coworkers and your customers start asking questions about usage and adoption, and customers start to ask for summary information on their data as well as just dumping their data. If you’re the only guy in charge of the database, this is often overwhelming.

Thankfully, we now have many options for what’s called self-service BI. The developer or DBA sets up the basic data models (say Orders) in an automated tool like SQL Server Reporting Services (SSRS) and then allows an information worker to select the columns, perform joins, and add filters to create reports. This basically cuts down miscommunication that can often happen between …

A new company often means new responsibilities and learning new ways of doing things. For a tech guy, it often means picking up a new framework or maybe if you are a glutton for punishment, a new language. I recently switched OSes, languages, and databases as a DBA/DB Developer. This was quite a massive shift for me. I went from the stable, enterprise database, SQL Server, to the little engine that could, MySQL. Before the switch, I would stew over the fact that SQL Server lacked features in comparison to Oracle or Postgres, but now I realize that there are far better things to worry about (such as non-blocking backups). I just wanted to go over some of the differences I found.

1. MySQL is a collection of binaries that manipulate data files. It is not a monolithic application that persists its data to disk, but instead it allows another process to manipulate its files even while it’s running. It interprets a folder in its data directory …

I learned how to use a computer on DOS and Windows. My first programming projects were written in QBASIC and my first Web applications were written in VB using ASP on Windows 2000. The first job where I made decent money was developing a SQL Server-based application. I bought my first car, an engagement ring, and a honeymoon with money from making software on Windows. Needless to say, I found a lot of intellectual and financial fulfillment from Windows over the years.

That first real job also allowed me flexibility in what technology I could employ, and I helped implement a features using Redis on top of Ubuntu. This was a fun time, because my company basically paid me to study a new technology and to gain experience using it. On my own, I began to use Linux and to embrace open-source ideas, one of which is that the consumer is also the producer. I changed my mindset about what it means to use software: for open-source projects, it often …

Even though I have come late to the party of professional development, relatively speaking, I am acutely aware of the conflict that seems to pervade the developer-DBA relationship. This is what I gather about why this is: DBAs used to be paid better that developers, and often this was because they were able to reduce the overall license and hardware costs of large database installations. Both the size and proprietary nature of databases made them incredibly expensive, so paying an individual gobs of money to make sure they ran efficiently and that the data was preserved was worth it.

Several trends have changed the playing field. The first is the arrival of small, commodity server hardware that makes mainframes or large servers unnecessary, and thus the cost is pushed down dramatically for most installations, while salaries for trained database professionals remained the same.

The second is the explosion of databases that do not (in …

Eric Ries' lean movement is picking up steam and is really extending agile software development to the wider organisation. Its interesting to see over time how some organisations have changed in a more competitive market in recent times. REA Group, the company I work for, have made some significant changes over the past few years including:

• Adopted the agile software delivery process throughout IT replacing the traditional waterfall method
• Slided and diced 'development / delivery' resources in different ways to provide accountability to the segment of the business they are working on
• Adopted a more collaborative approach between IT Operations and IT development/delivery

The traditional That being said, there are many companies that arrange teams like

…

I don’t want to post the link to this (perhaps, it was left public unintentional?) but here is what I stumbled upon recently. This is a log of production maintenance of IT systems in Perth, Western Australia (as far as I could say):

Good idea but shouldn’t companies keep this sort of information private?