Sql 在WHERE子句中计数还是有？

这基本上就是我想要达到的目标

SELECT 
COUNT(DISTINCT No) 
FROM 
Table 
WHERE 
(Type = 1 AND COUNT(DISTINCT No) > Num) 
OR (Type = 2 AND COUNT(DISTINCT No) > Num) 
GROUP BY
Week

实现这一目标的最佳方式是什么

谢谢

这是可能的答案。

使用以下选项：

SELECT 
COUNT(DISTINCT No) as num1
FROM TableName
WHERE Type IN (1,2)  
GROUP BY Week
HAVING num1 > Num

---

任何聚合比较都需要在Group By后面的HAVING子句中进行。请记住，根据您将非聚合条件放在何处，您可能会得到不同的结果，因为您将通过where聚合包含/排除的内容

即

可能不同于

SELECT COUNT(DISTINCT No) 
FROM Table 
GROUP BY Week
HAVING COUNT(DISTINCT No) > Num
AND Type = 1

---

如果你是按周分组，你肯定想知道计数是针对哪一周的

谢谢你的回答。我收到一条错误消息，说类型在Having子句中无效，因为它不包含在聚合中。。。我需要把它添加到组中吗？哦，这是一个很好的观点。后一条语句将不起作用，因为类型未按分组或它不是聚合。

SELECT COUNT(DISTINCT No) 
FROM Table 
WHERE Type = 1
GROUP BY Week
HAVING COUNT(DISTINCT No) > Num

SELECT COUNT(DISTINCT No) 
FROM Table 
GROUP BY Week
HAVING COUNT(DISTINCT No) > Num
AND Type = 1

  SELECT Week, Type, COUNT(DISTINCT No) WeekTally
    FROM   [Table]
   WHERE  Type in (1,2)
GROUP BY Week, Type
  HAVING COUNT(DISTINCT No) > @Num
ORDER BY Week, Type;