select t1,t2 from (select t1,t2 from test where t1 = '1' order by t2 desc) where rownum <= 3
union all
select t1,t2 from (select t1,t2 from test where t1 = '2' order by t2 desc) where rownum <= 3
union all
select t1,t2 from (select t1,t2 from test where t1 = '3' order by t2 desc) where rownum <= 3
union all
select t1,t2 from (select t1,t2 from test where t1 = '2' order by t2 desc) where rownum <= 3
union all
select t1,t2 from (select t1,t2 from test where t1 = '3' order by t2 desc) where rownum <= 3
分为新闻类型和新闻发布时间(整型)
类型为“体育”,财经,政治
目的想列出所有类型新闻最新发布的几条。感谢:snowy_howe(天下有雪) 不够我想要动态更新类型怎么办?
SELECT *
FROM (SELECT a.*,row_number() over(PARTITION BY t1 ORDER BY t2 DESC) rnum
FROM yourtable a
WHERE a.t1 = 1
OR a.t1 = 2
OR a.t1 = 3)
WHERE rnum <= 3
子句中不能用order by.