Question

我有一个包含ID列表的表，每个ID的状态为HW，HB，PIP或TBC。

我想计算每种状态的人数，所以我会看一张表格

HW HB PIP TBC

45 27 9 49

我的那一刻

    (SELECT COUNT(*) AS 'StatusHW' From HomeworkerStatus WHERE Status='Homeworker')
    UNION       
    (SELECT COUNT(*) AS 'StatusHB' From HomeworkerStatus WHERE Status='Home Based')
    UNION
    (SELECT COUNT(*) AS 'StatusPIP' From HomeworkerStatus WHERE Status='PIP') 
    UNION
    (SELECT COUNT(*) AS 'StatusTBC' From HomeworkerStatus WHERE Status='TBC')

返回

StatusHW

1 45

2 27

3 9

4 49

我也试过

    SELECT Status,
    sum(case when Status = 'Homeworker' then 1 else 0 end) StatusHW,
    sum(case when Status = 'Home Based' then 1 else 0 end) StatusHB,
    sum(case when Status = 'PIP' then 1 else 0 end) StatusPIP,
    sum(case when Status = 'TBC' then 1 else 0 end) StatusTBC
    FROM HomeworkerStatus
    GROUP BY Status

这会返回一个4x4表，其中包含行1,2,3,4和列Status，StatusHW，...，StatusTBC。这更接近我所追求的，但仍然不对。

任何帮助都将不胜感激。

由于

Answer 1

在汇总为：

时，只需删除已处理这些条件的group by

 SELECT 
    -- Status,
    sum(case when Status = 'Homeworker' then 1 else 0 end) StatusHW,
    sum(case when Status = 'Home Based' then 1 else 0 end) StatusHB,
    sum(case when Status = 'PIP' then 1 else 0 end) StatusPIP,
    sum(case when Status = 'TBC' then 1 else 0 end) StatusTBC
    FROM HomeworkerStatus
    -- GROUP BY Status

Answer 2

如果您只想要一行，请不要GROUP BY Status：

SELECT
sum(case when Status = 'Homeworker' then 1 else 0 end) StatusHW,
sum(case when Status = 'Home Based' then 1 else 0 end) StatusHB,
sum(case when Status = 'PIP' then 1 else 0 end) StatusPIP,
sum(case when Status = 'TBC' then 1 else 0 end) StatusTBC
FROM HomeworkerStatus;

如何在SQL中组合多个count语句

2 个答案: