本文章给大家介绍MySQL获取所有分类和每个分类的前N条记录,Article(Id,Category,InsertDate),现在要用SQL找出每种类型中时间最新的前N个数据组成的集合,一段不错的代码
代码如下 | 复制代码 |
SELECT A1.* FROM Article AS A1 INNER JOIN (SELECT A.Category,A.InsertDate FROM Article AS A LEFT JOIN Article AS B ON A.Category = B.Category AND A.InsertDate GROUP BY A.Category,A.InsertDate HAVING COUNT(B.InsertDate) ) AS B1 ON A1.Category = B1.Category AND A1.InsertDate = B1.InsertDate ORDER BY A1.Category,A1.InsertDate DESC |
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