November 29, 2014

Slow Query Log analyzes tools

(There is an updated version of this post here). MySQL has simple but quite handy feature – slow query log, which allows you to log all queries which took over define number of seconds to execute. There is also an option to enable logging queries which do not use indexes even if they take less […]

Joining Peter for MySQL Consulting

Starting September I’m leaving MySQL to partner with Peter on practice as well as work with him on some Web projects. I really enjoyed working under Peter’s guidance while working for MySQL and it is great we now can work together as a partners. I thanks MySQL for two great years I had. I also […]

Even minor upgrades are not always safe

I already wrote couple of weeks ago I keep most of my systems on MySQL 4.1 still as they will not benefit from MySQL 5.0 features anyway while I do not want to likely loose a bit of performance and possibly deal with new bugs and changes introduced in MySQL 5.0 (You never know where […]

GROUP_CONCAT useful GROUP BY extension

(There is an updated version of this post here) MySQL has useful extention to the GROUP BY operation: function GROUP_CONCAT: GROUP_CONCAT(expr) – This function returns a string result with the concatenated non-NULL values from a group. Where it can be useful?

ORDER BY … LIMIT Performance Optimization

Suboptimal ORDER BY implementation, especially together with LIMIT is often the cause of MySQL Performance problems. Here is what you need to know about ORDER BY … LIMIT optimization to avoid these problems ORDER BY with LIMIT is most common use of ORDER BY in interactive applications with large data sets being sorted. On many […]