Posts Categorized: Group Blog Posts
Welcome to the 88th edition of Log Buffer, the weekly review of database blogs.
No one has ever come out and formally asked me for a document that states “Best Practices to Scale Application X”. It is an unusual demand, since it’s something many of us at Pythian have implemented, but it’s been more of an ad hoc, iterative process — and rightly so, since architectures must be so organic, and so tailored to the application. What’s more, no one has ever brought us on board so early in the game that we have a hand in actually — gasp! — doing the design and data-model from the get-go. Woo hoo!
I’m amazed what people are able to do with Oracle technologies. One of the things I’ve liked the most is to spend some time (not enough!) with Kuassi Mensah. The guy is awesome! As a Product Manager at Oracle, he knows probably everything about JServer (the JVM in Oracle 11g), and he is one of the best guys on the subject of some of the key connection layer to access an Oracle database, including JDBC, OCI, and Web Services.
If you’re interested by any of those subjects, you should subscribe to his 360° blog and read his book.
I got to troubleshoot an amazing situation a few weeks ago. I think it is essentially inconceivable that allowing a single query to run on your system can flip another query’s plans and cause major performance issues (and in this case even downtime!). Sometimes it’s coincidence, sometimes it’s load, and sometimes it’s a single ad hoc query with a new predicate that starts the slowly-ticking time bomb. Here is how it happens and how to fix it.
Kenny Tilton posted about database troubleshooting, and he anecdotally illustrates and elaborates on a law of troubleshooting that I strongly agree with: Always solve the first problem. The corollary to his law is that “there only is the first problem.” I’m not sure I entirely agree with that one, but I will admit that that corollary is true at least 90% of the time, which is often enough to make it an incredibly useful insight.
I was recently asked a question by someone who had attended my Shmoocon talk entitled “Why are Databases So Hard to Secure?”. (PDF slides are available). I was going to put this into a more formal structure, but the conversational nature works really well. I would love to see comments reflecting others’ thoughts.
Welcome the the 87th of Log Buffer, the weekly review of database blogs.
Have you ever heard the one about throwing hardware at a software problem? I have this nifty RAC system that supports some very public and very mission-critical apps, and one day (it was Sunday night) it starts choking. We’re getting enqueues. Slowly they start climbing. Ten nodes came to a crashing halt. I have now seen a ten-node RAC cluster come to crashing halt and completely lock up. Why, you ask? A simple SQL statement: DELETE FROM a WHERE b=c AND d=e;.
Today is Hotsos Symposium 2008 Training Day — one full day with Tom Kyte. FInd out how I spent my last day at the Hotsos Symposium 2008.
I have been a MySQL DBA at The Pythian Group for three months (and 2 days) now. At most companies that is the probationary period, and I am still here, so that is a good sign….. So, after three months, how do I like it? Glad you asked!

Recent Comments