A daily report scanning 1.2 million rows to return two hundred. Why neither obvious index helped, what the composite one costs, and the two answers I turned down.
512 MB, 150 concurrent visitors, and a box that swaps before the CPU is busy. Replacing Apache and mod_php with nginx and PHP-FPM, in three stages that each…
long_query_time was an integer in MySQL 5.0, so one second became the conventional slow-query threshold and stayed there out of habit. It has taken a float since 5.1.…