(Kristian Nielsen) Today there was a question on the Freenode MySQL channel about a classical problem: Rows holding group-wise maximum of a column. This is a problem that I keep encountering every so often, so I thought I would write up something about it.

(Baron Schwartz) Peter wrote a post a while ago about choosing a good InnoDB log file size. Not to pick on Peter, but the post actually kind of talks about a lot of things and then doesn’t tell you how to choose a good log file size! So I thought I’d clarify it a little.

(Amit Kumar Saha) MySQL GUI Tools is a suite of graphical desktop applications for working with and administering MySQL servers. The suite consists of three tools: MySQL Query Browser, MySQL Administrator, and MySQL Migration Assistant (available only on Windows). We’ll look at the first two to see

(Leo Hsu and Regina Obe) This product is not specifically a PostgreSQL product but it is one that we use frequently with many of our database apps so we felt our obligation to blog about it in the context of databases. Lets face it, when you have a database, somebody will come to you one day and dem

(John Russell) I’ve always been intrigued by the FIRST_ROWS hint, so I paid special attention when we reached it in the 11g SQL Tuning class. But I’m still puzzled.

(Falko Timme) This tutorial explains how you can set up MySQL master-master replication on four MySQL nodes (running on Debian Etch). The difference to a two node master-master replication (which is explained here) is that if you have more than two nodes, the replication goes in a circle, i.e., with

(Barzan “Tony” Antal) Performance is something for which we all strive. This applies to the lives of DBAs too, since their first and foremost task is to achieve a high level of performance from their databases. SQL professionals cant stress enough that spending quality time to optimize both schema d

(Leo Hsu and Regina Obe) Sometimes when you are testing or setting up a server or just porting things to another server, you just want to install the same set of users as you had before without restoring any databases. In PostgreSQL, the users (Login Roles) and group roles are stored at the server l

(Sean Hull) MySQL has some powerful replication technology. It can be configured to replicate everything, or subsets of schemas or even individual tables. Those slave databases can themselves be masters as well, feeding still more databases a stream of transactions from the master.

(Shlomi Noach) When MySQLs root password is lost and must be reset, there are two popular ways to create a new password. One of the options is far too popular, in my opinion.