The listing of Dynamic System Variables on the MySQL Reference Manual’s page is supposed to show those variables you can change on-the-fly. The link at the top of this post, links to the 4.1 version of the manual, just in case folks are thinking I’m using a newer manual version. Mind you, I have this problem with 5.0.45 as well as 4.1.20.Read More >
Welcome to the 77th edition of Log Buffer, the weekly review of database blogs.Read More >
The “sla” in mysqlsla stands for “statement log analyzer”. This does a much better job than mysqldumpslow of analyzing your slow query log. This is really good for weeding out pesky entries in the slow query log that you do not care about. In this case, I’m using –slow to read the slow query log at the filename specified, –flat to flatten all the text to lowercase (basically case-insensitive matching) and –sort at to sort by “average time”.Read More >
I’ve been checking out a new client environment. My mission is to figure out some of the characteristics of the queries being run, and if they’re “good” or “bad”. In my arsenal of “tools I really want to check out” has been Maatkit’s Query Profiler, it profiles a batch of queries, without granularity (at least not the way I ran it) to see what query is doing what. So I ran this against a production machine, read my results hereRead More >
If you are wondering what the differences are between MySQL: SOUNDS LIKE and Full-Text search, look no further.Read More >
The Pythian family got a new song last Monday — “Sheeri” means “my song” in Hebrew. I’ve been working at Pythian for over a week now, and I really like the work model, environment and culture.The Pythian model of training is “jump right in, and ask questions when you don’t understand something.” The teams are very good technically, and people routinely help each other out. My teammates have been known to work on something I’ve been meaning to get to, and nobody utters a word of complaint. It’s a great workplace. There is a link to a post on my own blog explaining how I got the job.Read More >
With the popularity of multi-core machines (and innodb_thread_concurrency) on the rise, we are seeing more issues with adaptive hash index semaphore deadlocks. I guess there finally is a benefit to having MySQL Enterprise — the ability to disable InnoDB’s Adaptive Hash. If you want, you can hack the source code and compile your own version of MySQL. Only 4 file changes are needed to make the workaround happen, and the changes are detailed here.Read More >
Pythian is a global IT services company that specializes in designing, implementing, and managing systems that directly contribute to revenue and business success. We help companies adopt disruptive technologies to advance innovation and increase agility. Our highly skilled technical teams work as an integrated extension of our clients’ organizations to deliver continuous transformation and uninterrupted operational excellence.