mysql 查詢隨機若干數據

查詢隨機若干數據

SELECT
	`id` 
FROM
	`customer` 
WHERE
	id >= (
	SELECT
		floor(
			RAND( ) * (
				( SELECT MAX( id ) FROM `customer` ) - ( SELECT MIN( id ) FROM `customer` ) 
			) + ( SELECT MIN( id ) FROM `customer` ) 
		) 
	) 
ORDER BY
	id 
	LIMIT 20;