Question

我有下表 UserId [nvarchar（128）]，Rating [varchar（170）]：值大多为1,2,3，但可以有异常

评级包含3个值[1,2或3]

我希望得到类似

的结果

{{1}}

是否可以在单个查询中

Answer 1

为每个用户ID执行GROUP BY UserId计数。使用CASE分别计算1，2和3：

select UserId,
       count(case when Rating = 1 then 1 end) as [Count(1's)],
       count(case when Rating = 2 then 1 end) as [Count(2's)],
       count(case when Rating = 3 then 1 end) as [Count(3's)]
from tablename
group by UserId

Answer 2

在每个CASE和COUNT UserId中使用GROUP BY语句。

SELECT UserId, COUNT(CASE WHEN value = '1' THEN 1 END) AS [Count(1's)], COUNT(CASE WHEN value = '2' THEN 1 END) AS [Count(2's)], COUNT(CASE WHEN value = '3' THEN 1 END) AS [Count(3's)]
FROM yourtable
GROUP BY UserId

Answer 3

使用PIVOT：

SELECT
  UserId, 
  COALESCE([1],0) [Count(1's)],
  COALESCE([2],0) [Count(2's)],
  COALESCE([3],0) [Count(3's)]
FROM
  ýour_table
PIVOT
  (COUNT([Rating])  
FOR Rating
  in([1],[2],[3])  
  )AS p
ORDER BY 
  UserId

从表中为每种类型计算值

3 个答案: