(Robert Eisele) Calculating the standard deviation in MySQL is a no-brainer by using the build-in aggregate function STDDEV(). If you don’t need the original data and only want to save aggregated values in your database, the whole matter is getting more complicated – but is worth from a space and pe

(Todd Farmer) The recent release of 5.6.6 includes a new utility, mysql_config_editor, which makes it easier to interact with MySQL clients securely. At the same time, it’s easy to overstate the security benefits of using this new tool, and unfortunately, I think a couple of statements in the relea

(Shinguz) Recently a customer has shown up with some deadlocks occurring frequently. They were of the following type (I have shortened the output a bit):

(Shlomi Noach) Problem: you wish to write table data to file, but you wish to do so on client side.

(Ulf Wendel) An INSERT does not delay me much. At least, it does not necessarily block a PHP MySQL script immediately. The asynchronous query feature of the mysqlnd library helps out. A walkthrough what mysqlnd can do today and could do in theory.

(Rob Gravelle) If your MySQL database interfaces with applications or is used to generate reports then chances are good that it contains some massive stored procedures, just brimming with intensive logic and calculation code.

(Aleksandr Kuzminsky) Recently I had a case when a customer deleted the InnoDB main table space – ibdata1 – and redo logs – ib_logfile*.

(Leo Hsu and Regina Obe) In our last article, PL/V8JS and PL/Coffee JSON search requests we demonstrated how to create a PostgreSQL PL/Javascript stored function that takes as input, a json wrapped search request. We generated the search request using PostgreSQL.

(Anders Karlsson) You might have seen my attempts at testing MySQL as a Key Value Store (KVS) (here and here), i.e. used like MongoDB, and I have had some comments to those. Above all, many wanted to know the details of my test environment.

(Sean Hull) If you’ve never done point in time recovery, it’s time to take a second look. With a standard mysqldump you restore your database to the time when the backup happened. Only do them once a day, then you can lose as much as 24 hours of data.