mysql删除表中最旧的记录

Question

大家好我想要一个sql来删除数据库中最老的一行，目前我有这个：

DELETE FROM `videos` WHERE date_added IS NOT NULL LIMIT 1

这只会从我的数据库顶部删除还是会随机选择？

Answer 1

您可以使用order by并尝试这样 -

DELETE FROM `videos` WHERE date_added IS NOT NULL order by date_added desc LIMIT 1

了解更多信息：http://dev.mysql.com/doc/refman/5.0/en/order-by-optimization.html

Answer 2

您需要按日期，降序排序，因此第一个结果是最旧的结果，然后删除第一个结果。

DELETE FROM `videos` 
WHERE data_added IS NOT NULL 
ORDER BY date_added DESC 
LIMIT 1;

只要您的date_added列是MySQL日期类型或数字类型（例如Unix时间戳），此解决方案就会起作用。如果没有，您应该转换数据或修改数据库的结构（我建议稍后）。

为了投射数据，你可以这样做：

DELETE FROM `videos` 
WHERE data_added IS NOT NULL 
ORDER BY Cast(date_added as date) DESC 
LIMIT 1;

Answer 3

DELETE FROM `videos` order by date_added desc LIMIT 1

如果你只需要删除最旧的记录使用上面的查询，否则需要检查一些条件使用这一个

DELETE FROM `videos` WHERE date_added IS NOT NULL order by date_added desc LIMIT 1

Answer 4

一种方法是，您可以匹配最小日期值，然后可以删除记录。

DELETE FROM `videos` WHERE date_added = (SELECT min(date_added) from videos) AND date_added IS NOT NULL LIMIT 1

第二种方式，您可以使用order by子句删除。

 DELETE FROM `videos` WHERE date_added IS NOT NULL ORDER BY date_added ASC LIMIT 1

Answer 5

试试这个

DELETE FROM `videos` order by date_added DESC LIMIT 1

Answer 6

你也可以按id删除记录（如果它是自动递增的）

 DELETE FROM `videos` order by id DESC LIMIT 1

这将删除最后一条记录