quick selection of a random row from a large table in mysql

Question

What is a fast way to select a random row from a large mysql table?

I\'m working in php, but I\'m interested in any solution even if it\'s in another language.

Answer 1

Here's a solution that runs fairly quickly, and it gets a better random distribution without depending on id values being contiguous or starting at 1.

SET @r := (SELECT ROUND(RAND() * (SELECT COUNT(*) FROM mytable)));
SET @sql := CONCAT('SELECT * FROM mytable LIMIT ', @r, ', 1');
PREPARE stmt1 FROM @sql;
EXECUTE stmt1;