select spname from dingdan group by spname order by min(shtime) select spname from dingdan group by spname order by max(shtime)
select distinct spname from dingdan order by shtime asc就这样行了。没问题。
select t.* from tb t where not exists (select 1 from tb where dingdan = t.dingdan and shtime < t.shtime) order by t.shtime select t.* from tb t where not exists (select 1 from tb where dingdan = t.dingdan and shtime < t.shtime) order by t.shtime desc
曾经这么试过不行。order by字段跟distinct字段不一样。 学习楼上~
select distinct spname,max(shtime)from dingdan group by spname order by max(shtime)select distinct spname,min(shtime)from dingdan group by spname order by min(shtime)
select spname from dingdan group by spname order by max(shtime)
select distinct spname from dingdan order by shtime asc就这样行了。没问题。
学习楼上~
group by spname
order by max(shtime)select distinct spname,min(shtime)from dingdan
group by spname
order by min(shtime)