I was dinking around in PHPMyAdmin today and noticed this thing called "Propose table structure" which runs: SELECT * FROM `tablename` PROCEDURE ANALYSE ( ) ...and attempts to discover the most optimal fieldtype for each field, based on the data it's currently storing. You'll notice there are ENUMs just about everywhere. And a lot of its output is largely irrelevant. For example, in the watchdog table it recommends as the hostname field: ENUM('127.0.0.1') NOT NULL Which obviously would not be good. :P However, we do have a lot of TINYINT fields that are only ever going to store either 0 or 1, which could be changed to ENUM('0','1') NOT NULL as the analyzer recommends. Any MySQL gurus who could shed some more light on this? Is it worth doing? Would we gain any performance benefit from this or would it be too negligible to notice?