背景:用户浏览一个信息后会把此信息ID(如CoID)和此用户ID(如UserID)的信息保存成一条记录(有自增长字段);问题描述:现需要取6条最近浏览的信息,但是很多用户可能同时浏览同一条信息,单靠top是不行了,因为top之后出来的可能会是同样的6条信息;但是distince CoID 信息之后是排序好的CoID,还是不符合要求;希望:如果distince CoID 后,CoID还是原来的按照插入数据库时的排序就好了;另外应该还有其他办法,希望朋友们给点建议!谢谢!
调试欢乐多
top 6 *
from
(select * from tb t where not exists(select 1 from tb where CoID=t.CoID and id<t.id) order by id desc)
top 6 *
from
(
select
*
from
tb t
where
not exists(select 1 from tb where CoID=t.CoID and id<t.id) order by id desc))t
(SELECT * FROM TB T WHERE TIME=(SELECT MAX(TIME) FROM TB WHERE COID=T.COID))AS T ORDER BY TIME DESC
FROM
(SELECT * FROM TB T WHERE TIME=
(SELECT MAX(TIME) FROM TB WHERE COID=T.COID))AS T
ORDER BY TIME DESC