假设我有一个带有数字列的表(让我们称之为“score”)。

我想生成一个计数表,显示分数在每个范围内出现的次数。

例如:

score range  | number of occurrences
-------------------------------------
   0-9       |        11
  10-19      |        14
  20-29      |         3
   ...       |       ...

在这个示例中,有11行分数在0到9之间,14行分数在10到19之间,3行分数在20到29之间。

有什么简单的方法吗?你有什么建议吗?


当前回答

对于PrestoSQL/Trino应用Ken https://stackoverflow.com/a/232463/429476的答案

select t.range, count(*) as "Number of Occurance", ROUND(AVG(fare_amount),2) as "Avg",
  ROUND(MAX(fare_amount),2) as "Max" ,ROUND(MIN(fare_amount),2) as "Min" 
from (
  select 
   case 
      when trip_distance between  0 and  9 then ' 0-9 '
      when trip_distance between 10 and 19 then '10-19'
      when trip_distance between 20 and 29 then '20-29'
      when trip_distance between 30 and 39 then '30-39'
      else '> 39' 
   end as range ,fare_amount 
  from nyc_in_parquet.tlc_yellow_trip_2022) t
  where fare_amount > 1 and fare_amount < 401092
group by t.range;

 range | Number of Occurance |  Avg   |  Max  | Min  
-------+---------------------+--------+-------+------
  0-9  |             2260865 |  10.28 | 720.0 | 1.11 
 30-39 |                1107 | 104.28 | 280.0 |  5.0 
 10-19 |              126136 |   43.8 | 413.5 |  2.0 
 > 39  |               42556 |  39.11 | 668.0 | 1.99 
 20-29 |               19133 |  58.62 | 250.0 |  2.5 

其他回答

create table scores (
   user_id int,
   score int
)

select t.range as [score range], count(*) as [number of occurences]
from (
      select user_id,
         case when score >= 0 and score < 10 then '0-9'
         case when score >= 10 and score < 20 then '10-19'
         ...
         else '90-99' as range
     from scores) t
group by t.range
select cast(score/10 as varchar) + '-' + cast(score/10+9 as varchar), 
       count(*)
from scores
group by score/10

我会用一种稍微不同的方式来做,这样它就不必定义每种情况:

select t.range as [score range], count(*) as [number of occurences]
from (
  select FLOOR(score/10) as range
  from scores) t
group by t.range

没有测试过,但你懂的…

在postgres中(其中||是字符串连接操作符):

select (score/10)*10 || '-' || (score/10)*10+9 as scorerange, count(*)
from scores
group by score/10
order by 1

给:

 scorerange | count 
------------+-------
 0-9        |    11
 10-19      |    14
 20-29      |     3
 30-39      |     2

下面是如何在T-SQL中做到这一点:

DECLARE @traunch INT = 1000;

SELECT 
    CONCAT
    ( 
      FORMAT((score / @traunch) * @traunch, '###,000,000') 
      , ' - ' , 
      FORMAT((score / @traunch) * @traunch + @traunch - 1, '###,000,000') 
    ) as [Range]
  , FORMAT(MIN(score), 'N0') as [Min]
  , FORMAT(AVG(score), 'N0') as [Avg]
  , FORMAT(MAX(score), 'N0') as [Max]
  , FORMAT(COUNT(score), 'N0') as [Count]
  , FORMAT(SUM(score), 'N0') as [Sum]
FROM scores
GROUP BY score / @traunch
ORDER BY score / @traunch

因为要排序的列(Range)是一个字符串,所以使用字符串/单词排序而不是数值排序。

只要字符串有0来填充数字长度,排序在语义上仍然是正确的:

SELECT t.range AS ScoreRange,
       COUNT(*) AS NumberOfOccurrences
  FROM (SELECT CASE
                    WHEN score BETWEEN 0 AND 9 THEN '00-09'
                    WHEN score BETWEEN 10 AND 19 THEN '10-19'
                    ELSE '20-99'
               END AS Range
          FROM Scores) t
 GROUP BY t.Range

如果范围是混合的,简单地填充一个额外的0:

SELECT t.range AS ScoreRange,
       COUNT(*) AS NumberOfOccurrences
  FROM (SELECT CASE
                    WHEN score BETWEEN 0 AND 9 THEN '000-009'
                    WHEN score BETWEEN 10 AND 19 THEN '010-019'
                    WHEN score BETWEEN 20 AND 99 THEN '020-099'
                    ELSE '100-999'
               END AS Range
          FROM Scores) t
 GROUP BY t.Range