数据库表:
id topic_id post_date
1 1 2012-10-02
2 1 2012-11-03
3 2 2012-11-10
4 2 2012-11-04
5 3 2012-11-06
6 3 2012-08-06期望结果:id topic_id post_date
3 2 2012-11-10
4 2 2012-11-04
5 3 2012-11-06
6 3 2012-08-06
2 1 2012-11-03
1 1 2012-10-02按照topic_id分组, 然后每组内按照post_date排序, 整个分组按照组内第一个日期降序排列。
id topic_id post_date
1 1 2012-10-02
2 1 2012-11-03
3 2 2012-11-10
4 2 2012-11-04
5 3 2012-11-06
6 3 2012-08-06期望结果:id topic_id post_date
3 2 2012-11-10
4 2 2012-11-04
5 3 2012-11-06
6 3 2012-08-06
2 1 2012-11-03
1 1 2012-10-02按照topic_id分组, 然后每组内按照post_date排序, 整个分组按照组内第一个日期降序排列。
from tb
order by topic_id,post_date desc
from 数据库表 a
order by m desc,topic_id
跪求帮助
LRMXPeEroeOSfM72Q6gPJ/SSI1YvhHx3ldoLnaIVm8jSUGEBmOOzFmWOEJm8/EcKJFjG9G2dv75/UJGao3vukmVCvT4LK30d
由66个中文字 组成的数据。。你能解吗??
重金酬谢 谢谢 能解联系我 15085642252 QQ 85407665
本人有很多这样的数据需要解 1000元RMB 做为回报 绝不实言
select *
from tb
order by topic_id,post_date desc
e topic_id=a.topic_id) as m from t1 a order by m desc, topic_id;
+------+----------+------------+------------+
| id | topic_id | post_date | m |
+------+----------+------------+------------+
| 3 | 2 | 2012-11-10 | 2012-11-10 |
| 4 | 2 | 2012-11-04 | 2012-11-10 |
| 5 | 3 | 2012-11-06 | 2012-11-06 |
| 6 | 3 | 2012-08-06 | 2012-11-06 |
| 1 | 1 | 2012-10-02 | 2012-11-03 |
| 2 | 1 | 2012-11-03 | 2012-11-03 |
+------+----------+------------+------------+
6 rows in set (0.00 sec)
只取前3列就行。
select *
from tb
order by topic_id,post_date desc1楼的sql可以满足他的这个需求
+!