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?
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
select t.blah as [score range], count(*) as [number of occurences]
from (
select case
when score between 0 and 9 then ' 0-9 '
when score between 10 and 19 then '10-19'
when score between 20 and 29 then '20-29'
...
else '90-99' end as blah
from scores) t
group by t.blah
如果在MySQL中,请确保使用'range'以外的单词,否则在运行上述示例时会出现错误。
其他回答
select t.blah as [score range], count(*) as [number of occurences]
from (
select case
when score between 0 and 9 then ' 0-9 '
when score between 10 and 19 then '10-19'
when score between 20 and 29 then '20-29'
...
else '90-99' end as blah
from scores) t
group by t.blah
如果在MySQL中,请确保使用'range'以外的单词,否则在运行上述示例时会出现错误。
select cast(score/10 as varchar) + '-' + cast(score/10+9 as varchar),
count(*)
from scores
group by score/10
select t.range as score, count(*) as Count
from (
select UserId,
case when isnull(score ,0) >= 0 and isnull(score ,0)< 5 then '0-5'
when isnull(score ,0) >= 5 and isnull(score ,0)< 10 then '5-10'
when isnull(score ,0) >= 10 and isnull(score ,0)< 15 then '10-15'
when isnull(score ,0) >= 15 and isnull(score ,0)< 20 then '15-20'
else ' 20+' end as range
,case when isnull(score ,0) >= 0 and isnull(score ,0)< 5 then 1
when isnull(score ,0) >= 5 and isnull(score ,0)< 10 then 2
when isnull(score ,0) >= 10 and isnull(score ,0)< 15 then 3
when isnull(score ,0) >= 15 and isnull(score ,0)< 20 then 4
else 5 end as pd
from score table
) t
group by t.range,pd order by pd
另一种方法是将范围存储在表中,而不是将它们嵌入到查询中。你最终会得到一个表,命名为Ranges,它看起来像这样:
LowerLimit UpperLimit Range
0 9 '0-9'
10 19 '10-19'
20 29 '20-29'
30 39 '30-39'
查询如下所示:
Select
Range as [Score Range],
Count(*) as [Number of Occurences]
from
Ranges r inner join Scores s on s.Score between r.LowerLimit and r.UpperLimit
group by Range
这确实意味着要建立一个表,但是当所需的范围发生变化时,维护这个表是很容易的。不需要更改代码!
我在这里看到的答案在SQL Server的语法中行不通。我会用:
select t.range as [score range], count(*) as [number of occurences]
from (
select case
when score between 0 and 9 then ' 0-9 '
when score between 10 and 19 then '10-19'
when score between 20 and 29 then '20-29'
...
else '90-99' end as range
from scores) t
group by t.range
编辑:见评论