(Jim Tommaney) These examples abstract out the cost to access a given set of rows to highlight the relative cost to return (project) rows and columns. The assumption here is that the returned rows are generally contiguous.

(Sarah Sproehnle) Every time I teach the MySQL Cluster architecture, someone inevitably asks “Isn’t the management node (ndb_mgmd) a single point of failure?” The short answer: no. The management node is not a SPOF because the cluster can continue without it.

(Peter Zaitsev) Recently I had a chance to take a look at Redis project, which is semi-persistent in memory database with idea somethat similar to memcache but richer feature set.

(Darren Cassar) A colleague at work asked me “how can I run a case sensitive select on a case insensitive table?” out of curiosity and for a moment I hesitated, then said, yeah why not 🙂 ….

(Yoshinori Matsunobu) A couple of weeks ago, at a MySQL study group in Tokyo I presented about various kinds of MySQL hacking techniques, such as debugging with MS Visual Studio or gdb, tracing with DTrace, writing information schema plugins, accessing tables from UDF and storage engine API, and ext

(Ryan Thiessen) My first approach to diagnosing a performance problem is to start by trying to find the system’s bottleneck — the limiting factor in a series of events that causes a slowdown for the whole process.

(Sarah Sproehnle) In my years of teaching MySQL topics, I’ve noticed that many people write bad queries. It’s not necessarily their fault. It could be that they don’t understand some aspect of SQL, or that they solved the problem with the first technique that came to mind, or that their query is fin

(Baron Schwartz) You probably know that it’s possible to set configuration variables to log queries that don’t use indexes to the slow query log in MySQL. This is a good way to find tables that might need indexes.

(Rob Gravelle) Anyone who has spent a fair amount of time working with databases comes to realize that common tasks like backups and data transfers should be run from a script rather than interactively. Having MySQL read commands from a file is called running in batch mode, because such a file gener

(Baron Schwartz) Ever wondered how fast stored routines are in MySQL? I just ran a quick micro-benchmark to compare the speed of a stored function against a “roughly equivalent” subquery. The idea — and there may be shortcomings that are poisoning the results here, your comments welcome — is to se