我正在尝试将mysql中的中值计算转换为mssqlhttp://danielsetzermann.com/howto/how-to-calculate-the-median-per-group-with-mysql/
这是密码
SET @row_number:=0;
SET @median_group:='';
SELECT
median_group, AVG(height) AS median
FROM
(SELECT
@row_number:=
CASE
WHEN @median_group = gender THEN @row_number + 1
ELSE 1
END AS count_of_group,
@median_group:=gender AS median_group,
gender,
height,
(SELECT
COUNT(*)
FROM heights
WHERE a.gender = gender)
AS total_of_group
FROM
(SELECT
gender,
height
FROM heights
ORDER BY gender, height)
AS a)
AS b
WHERE
count_of_group BETWEEN total_of_group / 2.0 AND total_of_group / 2.0 + 1
GROUP BY median_group
就我所知
DECLARE @row_number integer, @median_group varchar(100)
SET @row_number = 0
SET @median_group = ''
SELECT
@row_number = (CASE WHEN @median_group = gender THEN @row_number + 1 ELSE 1 END) AS count_of_group,
(@median_group = gender) AS median_group,
gender,
height,
(SELECT COUNT(*)
FROM heights
WHERE a.gender = gender)
AS total_of_group
FROM
(SELECT
gender,
height
FROM heights)
AS a
ORDER BY a.gender , a.height
遗憾的是,我不知道如何克服这个错误—为变量赋值的select语句不能与数据检索操作结合使用。
任何帮助都是非常感激的
我知道有一些其他的方法来计算中位数是mssql特定的,但不知道如何进行这种转换是吃我。
非常感谢您的光临
1条答案
按热度按时间c6ubokkw1#
既然你能做这样的事情,为什么还要转换代码呢?
SQLServer有许多其他方法来进行这种计算。