我有一个SELECT语句是从一个CASE WHEN THEN状态计算出来的(或者可以使用多个IF语句)别名为'Length',我需要正确地将结果组合在一起。 SELECT似乎正在工作,但该组将它们分组错误。以下是我的发言:
SELECT CASE
WHEN DATEDIFF(o.EndDate, o.StartDate) < 30 THEN '<1 Month'
WHEN DATEDIFF(o.EndDate, o.StartDate) < 90 THEN '1 - 2 Months'
WHEN DATEDIFF(o.EndDate, o.StartDate) < 210 THEN '3 - 4 Months'
ELSE '>4 Months' END AS 'Length',
COUNT(DISTINCT(person.ID)) AS 'COUNT'
FROM person
INNER JOIN opportunity AS o
INNER JOIN Organization AS org
ON person.EntityID = o.id
AND O.OrganizationID = Org.ID
WHERE person.TitleID = 2
AND o.bID = 1
GROUP BY 'Length'
ORDER BY 'Length' ASC;
这会将所有结果分组为“3 - 4个月”,这是不对的..
答案 0 :(得分:36)
如果未将其包含在子查询中,则需要在CASE
子句中使用整个GROUP BY
语句。
SELECT CASE
WHEN DATEDIFF(o.EndDate, o.StartDate) < 30 THEN '<1 Month'
WHEN DATEDIFF(o.EndDate, o.StartDate) < 90 THEN '1 - 2 Months'
WHEN DATEDIFF(o.EndDate, o.StartDate) < 210 THEN '3 - 4 Months'
ELSE '>4 Months'
END AS `Length`,
COUNT(DISTINCT(person.ID)) AS `COUNT`
FROM person
INNER JOIN opportunity AS o
ON person.EntityID = o.id
INNER JOIN Organization AS org
ON o.OrganizationID = Org.ID
WHERE person.TitleID = 2
AND o.bID = 1
GROUP BY CASE
WHEN DATEDIFF(o.EndDate, o.StartDate) < 30 THEN '<1 Month'
WHEN DATEDIFF(o.EndDate, o.StartDate) < 90 THEN '1 - 2 Months'
WHEN DATEDIFF(o.EndDate, o.StartDate) < 210 THEN '3 - 4 Months'
ELSE '>4 Months'
END
ORDER BY Length ASC;
还删除ORDER BY
子句中列名称周围的单引号。
答案 1 :(得分:1)
您可以通过像这样引用它们来对 select 中的语句进行分组。另见this question。
SELECT CASE
WHEN DATEDIFF(o.EndDate, o.StartDate) < 30 THEN '<1 Month'
WHEN DATEDIFF(o.EndDate, o.StartDate) < 90 THEN '1 - 2 Months'
WHEN DATEDIFF(o.EndDate, o.StartDate) < 210 THEN '3 - 4 Months'
ELSE '>4 Months' END AS 'Length',
COUNT(DISTINCT(person.ID)) AS 'COUNT'
FROM person
INNER JOIN opportunity AS o
INNER JOIN Organization AS org
ON person.EntityID = o.id
AND O.OrganizationID = Org.ID
WHERE person.TitleID = 2
AND o.bID = 1
GROUP BY 1
ORDER BY 1 ASC;
答案 2 :(得分:0)
我正在努力解决完全相同的问题,这是我提出的解决方案:
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