SQL 十分位

 -- 十分位，这个算法不是很准确
 select
      family_agreement_cnt -- 字段
     ,dt                   -- 分区
     ,rn                   -- 排序
     ,cnt                  -- 总行数
     ,percent2             -- 分位值
     ,rk
     ,row_num
 from (
     select
          t1.family_agreement_cnt                   -- 字段
         ,t1.dt                                     -- 分区
         ,t1.rn                                     -- 排序
         ,t1.cnt                                    -- 总行数
         ,ceil(t1.rn / t1.cnt * 100)                                                  as percent2 -- 分位值
         ,row_number() over(partition by ceil(t1.rn / t1.cnt * 100) order by rn desc) as rk
         ,row_number() over(order by rn)                                              as row_num
     from (
         select
              family_agreement_cnt
             ,dt
             ,row_number() over(partition by dt order by cast(family_agreement_cnt as double)) as rn
             ,count(1)     over(partition by dt)                                     as cnt
         from table_name
         where dt=''
     ) t1
     where t1.rn = 1 or t1.rn % cast(t1.cnt/10 as int) = 0 or t1.rn = t1.cnt
     order by t1.dt,t1.rn
 ) t2
 where t2.rk = 1
 ;

 -- 方差
 select
     stddev(num) as std
 from (
     select 1  as num union all
     select 2  as num union all
     select 3  as num union all
     select 4  as num union all
     select 5  as num union all
     select 6  as num union all
     select 7  as num union all
     select 8  as num union all
     select 9  as num union all
     select 10 as num union all
     select 11 as num union all
     select 12 as num union all
     select 13 as num union all
     select 14 as num union all
     select 15 as num union all
     select 16 as num
 ) t1
 ;

 -- 这个算法更准确
 select
      t3.cookieid
     ,t3.createtime
     ,t3.pv
     ,t3.percent -- 分位值
     ,t3.pt      --分组内将数据分成N片
     ,t3.rn
     ,t3.cn
     ,t3.rn2
 from (
     select
          t2.cookieid
         ,t2.createtime
         ,t2.pv
         ,t2.pt  --分组内将数据分成N片
         ,t2.rn
         ,t2.cn
         ,row_number() over(partition by t2.pt order by t2.pv) as rn2
         ,ceil(t2.rn / t2.cn * 100)                            as percent -- 分位值
     from (
         select
              t1.cookieid
             ,t1.createtime
             ,t1.pv
             ,ntile(10) over(order by t1.pv)    as pt  --分组内将数据分成N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 ,'2015-04-15' as createtime, 14  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 15  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 16  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 17  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 18  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 19  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 20  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 21  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 22  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 23  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 24  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 25  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 26  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 27  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 28  as pv union all
             select 'cookie2' as cookieid ,'2015-04-15' as createtime, 29  as pv union all
             select 'cookie2' as cookieid ,'2015-04-16' as createtime, 30  as pv
         ) t1
     ) t2
 ) t3
 where t3.rn2 = 1 or t3.rn = t3.cn
 order by t3.rn
 ;