hive取等分数据

 %sql
 select
     t3.*
 from (
     select
         t2.*
         ,row_number() over(partition by t2.pt order by t2.pv) as rn2
     from (
         select
              t1.cookieid
             ,t1.createtime
             ,t1.pv
             ,ntile(2) over(order by t1.pv)     as pt  --分组内将数据分成2片
             ,row_number() over(order by t1.pv) as rn
             ,count(1) over()                   as cn
         from (
             select 'cookie1' as cookieid ,'2015-04-10' as createtime, 1   as pv union all
             select 'cookie1' as cookieid ,'2015-04-11' as createtime, 2   as pv union all
             select 'cookie1' as cookieid ,'2015-04-12' as createtime, 3   as pv union all
             select 'cookie1' as cookieid ,'2015-04-13' as createtime, 4   as pv union all
             select 'cookie1' as cookieid ,'2015-04-14' as createtime, 5   as pv union all
             select 'cookie1' as cookieid ,'2015-04-15' as createtime, 6   as pv union all
             select 'cookie1' as cookieid ,'2015-04-16' as createtime, 7   as pv union all
             select 'cookie2' as cookieid ,'2015-04-10' as createtime, 8   as pv union all
             select 'cookie2' as cookieid ,'2015-04-11' as createtime, 9   as pv union all
             select 'cookie2' as cookieid ,'2015-04-12' as createtime, 10  as pv union all
             select 'cookie2' as cookieid ,'2015-04-13' as createtime, 11  as pv union all
             select 'cookie2' as cookieid ,'2015-04-14' as createtime, 12  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 13  as pv union all
             select 'cookie2' as cookieid ,'2015-04-16' as createtime, 14  as pv
         ) t1
     ) t2
 ) t3
 where t3.rn2 = 1 or t3.rn = t3.cn
 ;