15

我想计算指定年份学生表中的男性、女性和学生总数。我希望结果可以以以下形式显示：

====================================
| Label    |  Value   |   Year     |
====================================
| Male     |   0      |   2013     |
| Female   |  23      |   2013     |
| Total    |  23      |   2013     |
====================================

如果指定年份没有男性/女性匹配，则查询应显示 0。知道我怎样才能做到这一点吗？

提前致谢

4

13 回答 13

24

考虑以下查询：

select
  max(registeredYear) as year,
  count(case when gender='Male' then 1 end) as male_cnt,
  count(case when gender='Female' then 1 end) as female_cnt,
  count(*) as total_cnt
from student
where registeredYear = 2013
group by registeredYear;

结果将是这样的：

Year male_cnt female_cnt total_cnt
---- -------- ---------- ---------
2013        0         23        23

您可以将此结果转换为您想要的形式。如果您想在查询中执行此操作，则可以这样做：

with t as (
    select
      max(registeredYear) as year,
      count(case when gender='Male' then 1 end) as male_cnt,
      count(case when gender='Female' then 1 end) as female_cnt,
      count(*) as total_cnt
    from student
    where registeredYear = 2013
    group by registeredYear)
select 'Male', male_cnt as male, year from t
union all
select 'Female', female_cnt as male, year from t
union all
select 'Total', total_cnt as male, year from t
;
于 2013-06-15T00:49:46.353 回答
5

你应该使用：

select name, COUNT(*)as tot, 
  COUNT(case when details.gender='male' then 1 end) as male,
  COUNT(case when details.gender='female' then 1 end) as female 
  from details  group by name
于 2014-10-26T11:03:05.573 回答
2

因为您不应该将网格格式与数据检索混为一谈

SELECT
  SUM(CASE WHEN gender = 'Male' THEN 1 ELSE 0 END) as MaleCount,
  SUM(CASE WHEN gender = 'Female' THEN 1 ELSE 0 END) as FemaleCount,
  COUNT(*) as TotalCount
FROM student
WHERE registeredYear = 2013
于 2013-06-15T03:12:43.843 回答
1

您的要求看起来很简单，但它有两个复杂性。第一个是一行是其他两行的摘要。这建议在查询中使用rollup或。grouping sets

第二个是即使您没有数据也需要有值。这建议使用“驱动程序”子查询。这样的子查询在分配值之前定义输出中的所有行。您将驱动程序表与left outer join.

一个未说明的要求可能是只提及一年一次。

以下查询方法将年度的最终表格放在一起。然后左加入摘要，从那里提取值（如果有）：

with year as (
      select 2013 as Year
     )
select driver.label, coalesce(s.value, 0) as Value, driver.Year
from ((select 'Male' as label, year from year
      ) union all
      (select 'Female' as label, year from year
      ) union all
      (select 'Total' as label, year from year
      )
     ) driver left outer join
     (select coalesce(Gender, 'Total') as Gender, year.year, count(*) as value
      from Students cross join year
      group by Gender with Rollup
     ) s
     on driver.year = s.year;

这假设性别表示为“男性”和“女性”，并且year数据中有一个称为列的列（没有样本输入或表格格式，人们必须猜测列名和样本值）。

于 2013-06-15T07:39:36.667 回答
1

我相信这与您只需通过学生表即可获得的效率一样高。只需根据需要更改 CTE 年份中的年份。

with
year as 
(
  select '2013' year
),
gender as (
  select 'Male' gender
  union all
  select 'Female' gender
)
select coalesce(g.gender,'Total') "Label", 
       count(s.gender) "Value", 
       y.year "Year"
  from gender g
  cross join year y
  left join student s
    on s.gender = g.gender
   and s.year = y.year
 group by grouping sets( (g.gender, y.year), (y.year) )
 order by case g.gender when 'Male' then 1 when 'Female' then 2 else 3 end
;

完全标准化的数据模型可能同时具有学年和性别表，因此不需要 CTE。（除非您真的想返回没有任何数据的年份的行）

这是一个没有学生 ID 和姓名的简单 sqlfiddle演示，因为它们与手头的问题无关。

于 2013-06-15T03:24:43.450 回答
1

像这样的东西：

select 'Male' as Label, count(gender) as Value from student where gender= 'Male'
union (
select 'Female' as Label, count(gender) as Value from student where gender= 'Female' )
union (
select 'Total' as Label, count(gender) as Value from student )
于 2013-06-15T00:50:20.330 回答
0

这是另一个变体，使用 UNPIVOT。这个专门搜索男性和女性，所以它不像我的另一个那样灵活（因为你需要对每个性别进行硬编码）。但这可能是最有效的。

WITH AllYears (RegisteredYear) AS
(
    --SELECT DISTINCT RegisteredYear
    --FROM Student

     --...OR...

    SELECT 2014
)
, GenderAndYearCounts AS
(
    SELECT RegisteredYear
        , SUM(CASE Gender WHEN 'MALE' THEN 1 ELSE 0 END) MaleCount
        , SUM(CASE Gender WHEN 'FEMALE' THEN 1 ELSE 0 END) FemaleCount
        , COUNT(*) YearCount
    FROM Student
    GROUP BY RegisteredYear
)
, GenderAndYearCountsForAllYears AS
(
    SELECT AllYears.RegisteredYear
        , ISNULL(MaleCount, 0) AS MaleCount
        , ISNULL(FemaleCount, 0) AS FemaleCount
        , ISNULL(YearCount, 0) AS YearCount
    FROM AllYears
        LEFT JOIN GenderAndYearCounts ON GenderAndYearCounts.RegisteredYear = AllYears.RegisteredYear
)

SELECT Label, Value, RegisteredYear
FROM 
(
    SELECT RegisteredYear, MaleCount AS Male, FemaleCount AS Female, YearCount AS Total
    FROM GenderAndYearCountsForAllYears
) allCounts

UNPIVOT
(
    Value FOR Label IN (Male, Female, Total)
) unpivotted
于 2013-06-15T02:13:42.083 回答
0

所有的性别，然后是所有的年份，然后是计数：

declare @Year int
set @Year = 2014

select labels.label,
    counts.cnt,
    @Year as registeredYear
    from 
        (select 'Male' as label, 1 as sortOrder
        union all 
        select 'Female', 2
        union all
        select 'All', 3) as labels 
   left join
       (select gender, 
        count(1) cnt
        from student
        where registeredYear = @Year
        group by gender) as counts
    on labels.label = counts.gender     
    order by labels.sortOrder
于 2013-06-15T02:18:27.640 回答
0

这对我有用。但是，在没有数据的年份里，它仍然无法为 M 和 F 显示 0 ：

Select * from 
(
SELECT isnull (SUM(CASE WHEN gender = 'M' THEN 1 ELSE 0 END),0) as Male,
       isnull(SUM(CASE WHEN gender = 'F' THEN 1 ELSE 0 END),0) as Female,
       registeredYear as 'year'

FROM student
WHERE registeredDate.Year = 2013 //could be a variable
group by registeredYear
 ) as s

 UNPIVOT
 ( 
value FOR gender IN (Male, Female) 
 ) Sub
于 2013-06-20T10:10:29.480 回答
0

试试这个，假设 Gender 或 RegisteredYear 中没有空值：

WITH AllYears AS
(
   SELECT RegisteredYear
   FROM Student
   GROUP BY RegisteredYear
)

, AllGenders AS
(
   SELECT Gender
   FROM Student
   GROUP BY Gender
)    

, AllGendersAndYears AS
(
   SELECT Gender, RegisteredYear
   FROM AllGenders, AllYears
)

SELECT Gender, RegisteredYear, CountForGenderAndYear
FROM AllGendersAndYears 
   CROSS APPLY 
   (
      SELECT COUNT(*) AS CountForGenderAndYear
      FROM Student
      WHERE Student.Gender = AllGendersAndYears.Gender
         AND Student.RegisteredYear = AllGendersAndYears.RegisteredYear
   ) countForGenderAndYear

UNION ALL

SELECT 'Total', AllYears.RegisteredYear, CountForYear
FROM AllYears
   CROSS APPLY 
   (
      SELECT COUNT(*) AS CountForYear
      FROM Student
      WHERE Student.RegisteredYear = AllYears.RegisteredYear
   ) countForYear
于 2013-06-15T00:53:28.213 回答
0

只需运行此查询...

SELECT 
     MAX(registeredYear) as Year
    ,SUM(CASE WHEN gender = 'Male' THEN 1 END) AS Male
    ,SUM(CASE WHEN gender = 'Female' THEN 1 END) AS Female
    ,SUM(CASE WHEN gender IS NOT NULL THEN 1 ELSE 0 END) AS Total
 FROM from student
 WHERE registeredYear = 2013
 GROUP BY registeredYear;
于 2013-06-15T00:49:53.513 回答
0 
select sp.CLASS_Name , count(*) as total 
     , sum( case when si.STDNT_GENDER = 1   then 1 else 0 end )    as Male
     , sum( case when si.STDNT_GENDER = 0   then 1 else 0 end )    as Female
  from SCHOOL_PLANE sp  inner join STUDENT_INFO si 
on  sp.CLASS_ID=si.STDNT_CLASS_PLANE_ID group by sp.CLASS_Name

-------
select sp.CLASS_Name , count(*) as total 
     , sum( case si.STDNT_GENDER  when  1   then 1 else 0 end )    as Male
     , sum( case si.STDNT_GENDER  when  0   then 1 else 0 end )    as Female
  from SCHOOL_PLANE sp  inner join STUDENT_INFO si 
on  sp.CLASS_ID=si.STDNT_CLASS_PLANE_ID group by sp.CLASS_Name
------------
select sp.CLASS_Name , count(*) as total 
     , count( case when si.STDNT_GENDER = 1   then 1  end )    as Male
     , count( case when si.STDNT_GENDER = 0   then 1  end )    as Female
  from SCHOOL_PLANE sp  inner join STUDENT_INFO si 
on  sp.CLASS_ID=si.STDNT_CLASS_PLANE_ID group by sp.CLASS_Name
于 2015-07-27T07:22:39.870 回答
-1

Select * from (select year, count(*) as total , sum( case when gender ='M' then 1 else 0 end ) as male , sum ( case when gender ='F' then 1 else 0 end) as female from mytable where year=2013 group by gender,year)
unpivot (income_component_value forincome_component_type in (male,female,total))

于 2019-09-09T21:04:19.920 回答