(Sergey Petrunia) In my previous post, I shared my finding that MySQL 5.6.7 does not make a cost-based choice between Materialization and IN-to-EXISTS strategies for subqueries, and why this is a problem.

(Alan Smithee) None of these are mine, just posted to remember them.

Along with lots of new features in performance schema, a new summary table, event_statement_summary_by_digest, has been added to MySQL 5.6. This tables gives a consolidated view of different statements executed/executing on MySQL server.

(Baron Schwartz) I was just skimming through the latest “Meet the Experts” podcast from Oracle, whose topic is debugging stored routines in MySQL. The tl;dr (tl;dl?) version is if you’re working with Windows and .NET, you can install a Visual Studio plugin that lets you debug stored routines in the

(Szymon Guz) PostgreSQL has many nice additional modules, usually hidden and not enabled by default. One of them is auto_explain, which can be very helpful for bad query plans reviews.

(banpei) It has been a while since I wrote on this blog. Basically I had too much on my mind (expanding my department, holidays, etc) to actually write here and I’ll promise to post more regularly from now onwards.

(Gabe Tucker) I don’t think this experience is unique. It has been shared repeatedly among those starting a job as a DBA (database administrator) at a new company, especially when the organization has never had a dedicated DBA. The conversation usually goes something like this:

(Ernie Souhrada) A few weeks back, I was working on a customer issue wherein they were observing database performance that dropped through the floor (to the point of an outage) roughly every 4 weeks or so. Nothing special about the environment, the hardware, or the queries; really, the majority of t

(gtowey) How many different ways can you get into trouble with replication? Most of them are obvious once they happen to you, but until they do you’re often not watching out for them. This is a list of all the ones I can think of, and most of them have happened to me at one point.

(Michael McLaughlin) My students wanted an example of how to use a lookup table in the database. I thought it would be a great idea to create a simple example like this one.