ID连续的情况下(注意不能带where,否则结果不好): - SELECT *
- FROM `mm_account` AS t1 JOIN (SELECT ROUND(RAND() * (SELECT MAX(id) FROM `mm_account`)) AS id) AS t2
- WHERE t1.id >= t2.id
- ORDER BY t1.id ASC LIMIT 4;
ID不连续的情况下: - SELECT * FROM `mm_account`
- WHERE id >= (SELECT floor(RAND() * (SELECT MAX(id) FROM `mm_account`))) and city="city_91" and showSex=1
- ORDER BY id LIMIT 4;
假设你的表叫做mm_account,并且有一个字段叫id。最快的方法如下(随机获取5条): - SELECT * FROM mm_account WHERE id >= ((SELECT MAX(id) FROM mm_account)-(SELECT MIN(id) FROM mm_account)) * RAND() + (SELECT MIN(id) FROM mm_account) limit 5;
如果带where语句,上面就不适合了。带where语句请看下面: - SELECT *
- FROM `mm_account` AS t1 JOIN (SELECT ROUND(RAND() * (
- (SELECT MAX(id) FROM `mm_account` where id<1000 )-(SELECT MIN(id) FROM `mm_account` where id<1000 ))+(SELECT MIN(id) FROM `mm_account` where id<1000 )) AS id) AS t2
- WHERE t1.id >= t2.id
- ORDER BY t1.id LIMIT 5;
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