表结构：ID, Category(类型), PubTiime(发布时间)

MS-SQL: 

SELECT t.*
FROM tb AS t
WHERE ID IN  (SELECT TOP 10 ID

                           FROM tb
                        WHERE Category = t.Category

                    ORDER BY PubTiime DESC)
ORDER BY t.PubTime DESC

SQLite:

SELECT t.*
FROM tb AS t
WHERE ID IN  (SELECT ID
                           FROM tb
                         WHERE Category = t.Category 
                     ORDER BY PubTime DESC
                        LIMIT 0, 10)
ORDER BY t.PubTime DESC